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Posted by cherrycat, Jul 25 2007, 09:16 AM
INSTALLING WINDOWS
Hardware Compatibility and Minimum Requirements
Hardware Compatibility
-list of devices that are designed to work perfectly with the OS
-HCL (Hardware Compatibility List)
-OS vendor gives the HCL
>helps to check hardware components compatibility or how well they perform with existing software
-needed to upgrade the OS
-helps decide if present hardware is good enough to handle new OS
-next thing check minimum hardware requirements to install or upgrade new OS
-Every OS is designed to perform better and do more things than existing one
-not recommended to ignore minimum requirements
>computer can become instable any time
Minimum hardware requirements for Windows 95
*x386 and 20 MHz or higher processor
*Microsoft Windows 3.0 or DOS 3.0 or later and OS/2 version 2
*8MB Recommended Memory
*70 MB Hard Disk space
*Floppy or a CD-Rom Drive
*Optional components like Mouse, Sound Card and Modem card
Minimum hardware requirements for Windows 98
*X486DX and 66 MHz or higher processor
*Microsoft Windows 3.5 or Windows 95
*24MB Recommended Memory
*140 to 355 MB of free Hard Disk space
*A Floppy or a CD-Rom Drive
*16 bit or 24 bit SVGA Card
*Optional components like Mouse, Sound Card and Modem card
Minimum hardware requirements for Windows ME
*Pentium 150-MHz processor or higher
*32MB RAM or higher
*320 MB free Hard Disk space or higher
*A Floppy, CD or DVD Drive
*Mouse or Compatible Device
*Video Adapter and Monitor that support VGA
*Optional components like Sound Card, Speakers and Head Phones
Minimum hardware requirements for Windows XP
*CPU with 300 MHz, Intel Pentium/Celeron family or AMD Athlon/Duron/K6 family
*128MB RAM
*1.5GB of free Hard Disk space
*Super VGA or Higher Video Adapter
*CD-ROM or DVD
*Keyboard or Mouse
<>Some additional components or services may need more resources. Also, Windows XP comes in many flavors. Go thorough the installation manual or contact the vendor<>
Minimum hardware requirements for Windows NT
*x486 with 33 megahertz (MHz) or higher, or Pentium, or Pentium PRO processor
*16 MB RAM
*125 MB Hard Disk space for Intel based computer and 160 MB for Non Intel based computer (RISC)
*Floppy or CD ROM Drive support
*VGA or SVGA Graphics support
*Keyboard and Mouse
<>retail version of Windows NT Server 4.0 supports up to four microprocessors out of the box. Support for up to 32 processors available from hardware vendor<>
Minimum hardware requirements for Windows 2000
*133 MHz or higher Pentium-compatible CPU
*64 MB RAM or higher
*2 GB hard disk with 650 MB free Disk space
*CD or DVD Drive
*VGA or higher Resolution
*Keyboard and Mouse
<>Windows 2000 comes in four different flavors. The above is for Windows 2000 Professional. contact the vendor or look at the web site of the vendor for info on other flavors<>
Disk Preparation
1. Back up all essential data to a CD or a storage device
2. Backup applications, if desired
3. Backup up device drivers if there's no installation disk
4. Make sure there's a boot disk or start up disk to install new OS
Partitioning
-depends on OS
-need boot disk
-choose which file system
>like FAT16, FAT32 or NTFS
-Partioning for FAT16 and FAT32
*Place boot disk into floppy drive and restart
*When computer starts from floppy it will install drivers for the CD-ROM
*After booting is completed there'll be a DOS prompt a:\>
*type FDISK and enter
*choose 'Y' or 'N' for large disk support
-'N' means it will be limited to FAT16 with a partition size of 2 GB
-'Y' for large disk support then it will have FAT32 that does not have such limitations
*next screen will have a menu with a number of choices
-for a new hard disk choose option 1 for creating a primary partition
-select 3 for a used hard disk for deleting the partition
*If 1 is chosen then on next screen select 1 for primary boot partition
*specify size of partition or give the % of the disk space for the primary drive
-for only one partition give 100%
-for more than one, create extended partitions and logical partitions
*to create extended partitions select go back to the first screen by pressing the Esc key
-option 1 then select Create Extended partition on next screen
*create logical partitions next
-will be prompted to create logical partitions after the extended partition is created
-make any number of logical partitions and specify disk space for each logical drive
*once done, press Esc to come out of FDISK
Format Drive
-After partitioning, format
-makes disk usable to store data on
-boot the computer from the bootable disk after partitioning
-use format command at the MS-DOS prompt
>erases everything
E.g.
Format C:
Switches
FORMAT <drive:> [/V[:label]] [/B] [/S] [/C]
<drive:> drive letter of the drive being formatted
[/V[:label]] refers to the label or name given to the drive to be formatted
[/B] "B" switch, used to allocate space on the drive for insertion of system files
[/S] used to transfer the system files to the newly formatted disk in order to enable it to be booted or started
[/C] used to check and verify any clusters on the drive that have been previously marked as bad
Installation Method
-for a blank hard disk or new disk OS must be installed from scratch
-vendors provide boot disk or startup disk
-two choices
1. run entire setup from a single CD
2. use a bootable floppy or installation disks
-Win98 and beyond, all installation can be done with a single CD
-CD is capable of booting and preparing the computer for installation
-some versions of Windows 95 need a boot disk or startup disk and an installation CD
other installation methods
*Upgrading an operating system
*Installing the OS from a network or remote location
Network installation is for a computer that participates in a network. If you are in a network then you need to have a Network Card capable of wake on LAN capabilities.
Upgrading has many advantages
1. don't have to format and partition
2. don't have to back up
3. keep old settings and applications
4. more features than the present OS
5. can roll back to the previous version of OS any time if there are problems
-will need an upgrade CD
Network Installation
-avoids installing the OS in each computer individually
-configure the client to the server and the server will install the OS
-Multiple instances of installations will happen in parallel
-can also automate certain parts of installation where menu options are chosen or answer certain questions
-options are provided in a file and the computer will pick up the answer from that file and install the OS
Bootable CD
-when comp is started it looks for the boot device to load the OS
-in normal operation this is done from hard drive
-when POST is completed the computer searches for the boot disk or bootable hard drive
-with OS it will boot from hard disk if not it will throw an error- <>No bootable device found<>
-boot disk contains certain necessary files or that helps the computer load the OS
>Command.com
>MSDOS.SYS
>IO.SYS etc.
-boot disk is a handy tool
-can help boot the computer even without the hard disk
-can be a CD or a floppy disk
How to Boot from bootable Floppy or CD
1. Place the boot floppy/CD in the respective drive
2. Restart and go into setup or CMOS and change the bootable device to floppy or CD
3. Save the changes and restart
4. there will be displayed a choice of bootable menu
5. Select and wait until the booting is complete
6. will see the DOS prompt at the end of booting
Windows 95
1. Click Start >> select Settings >> select Control Panel
2. In Control Panel Window, double click Add/Remove Programs
3. From Add/Remove Programs dialog box, select startup disk >> click make new disk
when prompted to insert the disk, insert the disk and complete the installation
Windows 98 and ME
-much the same as for Windows 95 except that Win 98 and ME support CDROM drive disk
-many utilities apart from the boot files
Windows NT:
1. Insert the Windows NT CD in the CDROM
2. access the i386 folder located in Windows NT directory
3. Insert a formatted floppy disk in floppy drive
4. Copy boot.ini, ntdetect.com and NTLDR files from the i386 folder to floppy disk
Windows 2000:
1. 4 formatted floppy disks and a 2000 CD
2. Put CD in drive
3. Browse the CD and locate the boot disk folder and double click makeboot.exe and click OK
Windows XP:
1. Put floppy disk in computer
2. Open My Computer and right click the floppy drive and click on format
3. In format window check create an MS-DOS startup disk
4. Click Start
<>With Windows XP Microsoft has been phasing out the Floppy drive and is promoting CD based boot disk. go to Microsoft's web site and download the CD version of the boot disk.<>
Installation
-after formatting is installing
-first starts from the command line then goes to GUI mode then finally setting up devices and installing drivers
-big difference in installing Win9x operating system and Windows NT, 2000
Installing Windows 98(and all 9x and ME)
-three major versions of 98 available
1. Windows 98 Original Version
2. Windows 98 OEM Edition
3. Windows 98SE
-has Internet Connection Sharing(ICS)
Prerequisites
1. Partition and chose a file system either FAT16 or FAT32
2. Create Active Partition
3. Format drive
4. Keep Windows 98 Startup disk handy
5. will need a motherboard installation disk if the chipset is from Intel like i810, i820 etc
-needed in the last part of installation
6. Keep device drivers handy
7. Disconnect external devices
Installing Part-I
*Start from the Setup disk
-there will be two options
1. Boot from hard disk
2. Boot with CD-ROM support
-choose option 2
*make a note of the drive letter assigned for the CDROM drive
-Windows 98 will create a virtual drive and load the tools needed
>drive letter E
>After installation the virtual drive will disappear
* At prompt (a:\) modify the drive letter to the virtual drive created i.e., e:\
-represents CDROM drive
-Type setup and press enter (E:\ setup)
>setup program will perform a routine check
-runs Scandisk
-checks the file systems and directory structure
-notifies of errors
-gives a log file that is a report of the check
*setup will initialize the system and copy all of the related files necessary
*There will be a setup screen which shows information of what is going on and the features of the OS
-left side displays the five setup steps with the time left
1. Preparing to run Windows 98.
-Setup prepares the Windows setup wizard
*Initially, displays the Windows 98 Setup dialog box
*creates setuplog.txt file in root directory
*detects the drive where OS will be installed and the location of installation files
*creates temporary directory in root called Wininst0.400 and copies Mini.cab to it
-holds the mini-Windows program files needed by setup
*all the files are extracted in Precopy1.cab and Precopy2 located in the source files (installation disk) Wininst0.400
-required for the Setup Wizard
2. Collecting information about computer
*License Agreement screen
*Product Key screen
*Select a directory for installing
*pick the type of Setup wanted
-Typical, Portable, Compact, or Custom
*enter your name and company name, as applicable
*choose 'install the most common components or customize your selection'
-likey select install most common
*identify computer for networking
-select the location to get region-specific information from Internet
*create the Startup Disk if desired
*setup will start copying files
3. Copying files to the computer
-Don't interrupt setup here or stop the program
-would have to rerun the entire process again as all the files would not have been copied
4. Restarting computer
On completion of copying of the Windows 98 files on to the computer, you will be prompted to restart the computer. You can either click on the Restart Now button to restart immediately, or wait for 15 seconds and leave the setup to restart the computer automatically. Remove the boot disk from the drive. You will see this message when the computer restarts:
Do not interrupt the setup here or do not stop the program. If you do that you will have to rerun the entire process again as setup would not have copied all the files necessary to carry out installation.
5. Setup Hardware and Finalize the settings
-setup configures
*Control Panel
*Programs on the Start menu
*Windows Help
*MS-DOS Program Settings
*Tuning Up Application Start
*Time Zone
*System Configuration
-restart once configuration is done
-for a domain it will ask for user name and password
-after restart setup will finalize installation
*Builds driver information database
*Updates System Settings
*Personalized settings like settings for IE, Start Menu, Online Services, volume control, and Channels
-setup displays the 'Welcome Screen'
<>screen may look dull and most devices may not work
-have to install the device drivers and clear the Device Manager
Installing Windows 2000 Professional
-prerequisites for installing Windows 2000
1. check hardware configuration
-use HCL to check for compatible devices
2. have the device drivers for Windows 2000
3. partition and format
-minimum 1 GB
4. installation disk
5. for a network installation have a network card with network booting capabilities
Installing
*Put CD in the drive and reboot
*there will be a blue screen with setup
-setup will be copying files, which takes time
*next screen is Welcome Screen
1. To Setup Windows, press enter
2. To Repair, press r
3. To Quit, press F3
*Enter shows License Agreement
-Read and press F8 to accept
*shows existing partitions and un-partitioned space
-create partitions by pressing C
-delete by pressing D
>if not partioned already
*select the partition and press enter
*Select format with NTFS option and enter
*will show formatting taking place
1. Setup examines disk after format
2. copies files to installation folder
3. reboot
-remove any floppies press enter to reboot
-will do it it's self in 15 seconds
4. After reboot it will tell you toenter any key to boot from CD
-Do not press a key and wait for the computer to start from hard disk
5. 'Windows is starting please wait'
6. wait for mouse to activate
7. setup gathers information about comp
-Press enter to continue
8. begins installing devices
<>
1. Regional Settings and Keyboard layout
-default is English (United States)
-customize to select the language, numbers, time and date
2. select input locale
-customize the keyboard settings to the language wanted
-default English US
3. press the continue button
-give a name and organization
4. product key
-25 characters long found on the back of the packaging disk
5. computer name and administrative password
6. Time Zone and area
<>
1. network selection
2. next screen are two choices
*Typical Settings
-automatically installs clients for Microsoft networks, file and print sharing for Microsoft settings and TCP/IP protocol suit with automatic addressing
*Custom Settings
-choose to manually install wanted network software
3. part of a domain or a standalone system (workgroup) If part yes then give the domain name and the computer will ask for credentials to complete the task. For now select 'No' and proceed.
4. configure
-final tasks
1. start menu
2. Registering components
3. Saving settings
4. Removing temporary files from setup
-tick mark against each as finished
5. once done will ask to remove installation disk and restart
<>
1. network setup wizard-click next
2. login with user name and password given during setup
3. Select User must enter user name and password, for multiple users
4. Click finish
5. Ctrl+Alt+Del will launch logon screen
-Yay, Windows 2000 desktop!
Installation Options
-options for setup
1. Drive to install to
2. File System: FAT16, FAT32 and NTFS
3. Directory
-default is C:\
4. Regional Settings
5. Installation types
-Typical or Custom
6. Network Settings
-Typical or Custom
7. Dual Boot support
8. Work Group or Domain
Installation type (Typical/Custom)
-define behavior and options available
-Default is Typical
four choices
1. Typical
-easiest setting
>computer selects default options, asks minimum questions
>can add other components later
>>Add/Remove Programs>>Windows components
>Windows 2000, has separate tabs for more network and services
2. Portable
-mobile users or laptop
>roaming profile and advanced power management
3. Compact
-smallest
>upgrading and if HD has little free space
-no optional components
-add components manually later
4.Custom
-advanced users or administrators
-choose optional components
>Components Tab >> check box for component
Network Configuration
-join a domain or a workgroup
>workgroup for stand alone
-domain needs user account created for the comp in the domain
-If connected to network need
* Name of comp
*Name of workgroup or domain
*TCP/IP address if there is no Dynamic Host Configuration Protocol [DHCP]
File System
-Windows 3.x, 95 and 98 use FAT16 or FAT32
-NTFS for Windows NT, 2000 and XP
NTFS
capabilities of FAT and more advantages
*Better File Security
*Better Disk Compression
*Support for large Hard Disk
-support 2 terabytes
-dual boot with Windows 9x and Windows 2000
>Windows 9x can't read
FAT 32
-enhanced FAT 16
-HD with 512 MB to 2 TB
-more compatibility with OSs
-for dual-boot configuration use FAT 32
FAT16
-designed for MS-DOS
-slow
-can't use big partitions
>2GB
-Windows 3.x and Windows 95
Dual Boot Support
-considerations for dual boot
*Each OS gets own partition
*Windows 9x operating system and WinNT/2000/XP use FAT file system
-Windows 9x can't read NTFS
*Don't install Windows 95 and 98 in dual boot
-Windows 98 is upgrade version of Windows95
>will try to use same boot file
*When you are installing Windows 95 and Windows 2000, install Windows 2000 last
-files necessary to start Windows 2000 could be overwritten
-usually install high end OS last
>for Windows 98 or 2000 can install in any order but best to install higher OS last
*to install Windows NT and Windows 2000 install service pack 4 for Windows NT
-Windows 2000 is NTFS 5 and Windows NT is NTFS 4 so won't read 2000 partitions
*can't share applications in dual boot
-must be installed on both
Device Driver Configuration
-Device drivers installed in the final phase of installation
-plug and play should detect devices and install drivers
>>will ignore device if driver not found
>>yellow exclamation mark in device manager
-Plug and play eases install of new devices
-Hot plug devices in Windows 2000 and XP
>automatically detects the presence of a new device and loads device drivers
>>make sure device supports plug and play and is compatible
-If device is not installed go to device manager and install devices manually
to use the plug and play feature one of these is needed
*An Advanced Configuration and Power Interface (ACPI) BIOS
*A Plug and Play BIOS
*Plug and Play compliant hardware devices (including buses)
Upgrading
-retain your present settings, application and user data
-adds more features and security
Windows 9x to Windows XP
1. present OS can be upgraded?
2. hardware requirements?
3. file system support?
4. device compatibility?
5. present applications support upgrade?
6. have upgradeable version of OS CD?
7. if doesn't work well roll back or uninstall the upgrade
Upgrading Windows 9x/ME to Windows XP
XP supports old file systems->FAT16 and FAT32 ->new file system, e.g. NTFS5
-must meet the hardware requirements for XP
1. close all the programs and running applications
2. Boot up
3. put XP CDROM in the CDROM drive
-Windows XP installation screen
4. Select upgrade option
5. next screen select Upgrade
-to overwrite OS or for dual boot->clean install
6. Windows XP License agreement
7. product key
8. upgrade report
-note points related to hardware or software issues
9. may update from internet using Dynamic Update Technology
>Microsoft updates XP drivers and patches a lot
10. setup copies more files and reboots
-don't press a key if there is a message to press any key
11. installs network and devices, Start Menu, components registered
12. program and system settings upgraded
-settings saved
-temporary files deleted
-system reboots again
Upgrading Windows NT, 2000 to XP
1. Boot NT/2000
-put in Windows XP CDROM
-Install Windows XP
2. select upgrade to Windows XP
-clean install overwrites all
3. License Agreement(F8)
-product key
4. update with Dynamic Update Technology(internet)
5. upgrade report
-note hardware or software issues
6. updating the boot files
-reboots automatically
7. copies more files
-reboots self the computer
-do not press any key
8. installs network and devices
-Start Menu is installed
-components registered
9. program and system settings upgraded
-settings saved
-temp files removed
-system gets rebooted
Determine correct startup Utility (WINNT 32 Vs WINNT)
Winnt32
-performs installation or upgrade to XP
-winnt32 can be run at command /w Win 9x and beyond
-WINNT.EXE and WINNT32.EXE used to run XP installation program from command line
-WINNT used for booting from DOS or boot disk
-located in i386 folder in root directory of CD drive of installation
Syntax
-winnt32 [/checkupgradeonly] [/cmd:<command line>] [/cmdcons] [/copydir:<folder name>] [/copysource:<folder name>] [/debug[<level>][:<file name>]] [/m:<folder name>] [/makelocalsource] [/noreboot] [/s:<source path>] [/syspart:<drive letter>] [/tempdrive:<drive letter>] [/udf:<ID>[,<UDB file>]] [/unattend[<seconds>][:<answer file>]]
WINNT.EXE
-perform clean ("full") install of XP in MS-DOS or Win 3.x
-existing installation of MS-DOS/Windows 3.x or a boot disk
-can't upgrade existing version of Windows to XP
Syntax
-winnt [/a:] [/e:<command>] [/r:<folder name>] [/rx:<folder name>] [/s:<source path>] [/t[:<temp drive>]] [/u[:<answer file>]] [/udf:<ID>[,<UDB file>]
Application Compatibility
-Often, applications developed for earlier versions of Windows do well on Win 2000 and XP
-not always, need to be tested
*Setup and Installation, Configuration, Version Checking
*User Interface
*Hardware, Input, Output, Threading
*Networking and Security
*General Programming Techniques
Application Compatibility Toolkit
-ACT
>set of program utilities and related documents for checking compatibility among application programs in Win OSs
>especially in large network
>diagnose and fix compatibility problems
-Win 2000 with Service Pack 3 or later, XP, and Windows Server 2003
consists of
*Application Compatibility Analyzer to pinpoint compatibility issues
*Application Verifier used during development to be sure there are no compatibility issues
*Compatibility Administrator used to select and apply specific compatibility fixes and use fixes on other comps
Apply service packs, patches and updates
Service pack
-collection of patches and updates combined in single package
-tested as a package for greater system stability
-downloaded or ordered
Windows Update
-online extension of Windows to keeps computer up-to-date
Boot Sequence
-when comp is booted CPU runs instruction located at memory location FFFF0h->boot sector of BIOS
>jump instruction to transfer execution to where BIOS start-up program is
>Power-On Self Test (POST) is run check devices
-BIOS looks for bootable device
>if device not found an error is thrown and boot process halts
>>if found loads and executes boot sector
-in hard drive referred to as the master boot record (MBR)
>MBR code verifies partition table for an active partition and when found, loads partition's boot sector and executes
-OS specific
-main function is to load and execute kernel that continues startup
-if no active partition or if active partition's boot sector is invalid MBR loads secondary boot loader and gives control to it
>partition (mostly via user input) is selected by secondary boot loader and its boot sector is loaded which loads corresponding OS kernel
Boot Steps for Windows 9x System
two parts
-Boot strap process
-Master boot record and boot sector
ROM BIOS Bootstrap Process
*Run POST routines
*Read master boot record and partition table
*Plug and Play BIOS verifies RAM for I/O port addresses IRQs, DMA channels, and other settings needed to configure Plug and Play
*Disabling Plug and Play devices
*Creating map of used and unused resources
*Plug and Play devices configured and re-enabled, one at a time
-Plug and Play devices initialized using default settings when comp is started if Plug and Play BIOS is not found
*MBR finds boot partition by reading partition table at end of MBR
*control is passed to boot sector in partition that has disk boot program
*boot sector copies IO.sys file from root directory into memory
Boot Steps for Windows NT/2000
Before boot sequence
*POST run
*boot device is found
-MBR loaded into memory
-active partition boot sector is found
>>loaded into memory
*NTLDR loaded into memory from boot sector
*The processor is switched from real mode into 32 bit flat memory mode by NTLDR
*starts minifile system drivers
-FAT, FAT 32 (2000 only) or NTFS
*reads BOOT.INI file
-displays Boot Loader Menu
-in dual boot system, if OS other than NT is selected, BOOTSECT.DOS is loaded and control passed on to it for booting
*If Windows NT/2000 is selected, NTLDR will run NTDETECT.COM
-scans hardware and passes information back to NTLDR
*loads NTOSKRNL.EXE, HAL.DLL, and SYSTEM hive
Kernel Load Phase
*NTLDR initiates NTOSKRNL.EXE
*HAL (hardware abstraction layer) loaded
-hides physical hardware from applications
*SYSTEM hive is loaded and scanned for device drivers along with services to be loaded
-organized into groups and loaded into memory but not yet initialized->in order in which they appear in ServiceGroupOrder subkey of registry
Kernel Initialization Phase
-screen is blue
-kernel and drivers that loaded during the kernel load phase initialized
-kernel is initialized
*SYSTEM hive scanned oagain to decide which drivers are to be loaded
-drivers initialized
Services Load Phase
-initiates Session Manager, SMSS.EXE
-runs programs that listed in BootExecute Registry entry
-starts needed subsystems
Win 32 Subsystem Start Phase
-automatically initiates WINLOGON.EXE->starts Local Security Authority LSASS.EXE and displays Ctrl+Alt+Delete logon dialog
-Service Controller (Screg.exe) checks Registry for services marked to load automatically and loads them
User Logon
-Boot is not considered good until user logs on successfully
Posted by cherrycat, Jul 13 2007, 10:35 AM
COMMAND LINE & OS UTILITIES
Command Line Functions
-method of interacting with a computer by giving it lines of textual commands as input from the keyboard
>type the commands on the command prompt
-e.g. "C:\WINDOWS>"
>C: indicates that user is in the C drive
->C usually reserved for the internal hard disk of a PC
-open a command prompt / interpreter
*Windows 95 / 98:
Select Start >>Run >> type "command >>" click OK to open command interpreter.
*Windows NT / XP / 2K:
Select Start >> Run >> type “cmd >>” click OK to open command interpreter.
<>use the EXIT command to stop command interpreter and return control to windows environment<>
ATTRIB
display or change, or remove the file attributes like Read-Only, Archive, System, and Hidden attributes assigned to files or directories
Syntax
ATTRIB [+R | -R] [+A | -A] [+S | -S] [+H | -H] [ [drive:] [path] filename] [ /S]
Where [+R | -R] [+A | -A] [+S | -S] [+H | -H] are the 4 flags that can be set by ATTRIB
R-Read Only
A-Archive
S-System
H-Hidden
turned on by the + (plus sign) and off by - (minus sign)
-ATTRIB typed alone displays the attributes of all files in the current directory
-hidden files are displayed
-displays information not revealed by DIR
-ATTRIB and a filename will display attributes of that file
E.g.-ATTRIB C:\TEST.BAT
-ATTRIB +H C:\TEST. TXT will turn hidden flag on
-ATTRIB -H C:\TEST. TXT will turn hidden flag off
Command/CMD
-starts a new instance of command interpreter
Syntax
-COMMAND [[drive:]path] [device]
Switches
/C command
-specifies command interpreter is to perform the specified command and then exit
E:xxxxx
-specifies the environment size in bytes indicated by xxxxx
/K command
-runs the specified command, program, or batch program
>then displays command prompt
->must be the last switch on the COMMAND command line
/Y
-directs COMMAND.COM to step through the batch file specified by the /C or /K switches
-useful for debugging batch files
COPY
-copies one or more files to a specified location
-also can be used to combine files
Syntax
-COPY [ /A | /B ] source [ /A | /B ] [+ source [ /A | /B ] [+ ...] ] [ destination ] [ /A | /B ] ] [ /V ] [ /Y | /-Y ]
Switches
/A-ASCII text file
/B-binary file
/V-Verifies new files are written correctly
/Y-Suppresses prompting to confirm you want to overwrite an existing destination file
/-Y-Causes prompting to confirm you want to overwrite an existing destination file
E.g.-copy *.* a
-copies all files in current directory on to a floppy disk in drive a:
DEFRAG
-disk defragmenter
>software utility designed to reorganize files in chronological order to optimize disk performance
->places each program together at one place instead of scattered fragments
->>allows the read-write head to access data faster
-Windows 98 has an improved version of defrag
>places the most commonly accessed data at the beginning of the drive
Syntax
-DEFRAG [ drive: ] [ /F ] [ /U ] [ /B ] [ /SKIPHIGH ] [ /LCD | /BW | /G0 ] [ /H ]
Switches
/F-Defragments files and ensures that disk contains no empty spaces between files
/U-Used to defragment files, leaving empty spaces between files
Delete/Rename
Del
-Used to delete specified files
Syntax
-DEL [ drive: ] [ path ] filename [ /P ]
Switch
/P-Prompts for confirmation before deleting
E.g.
-del c: \ windows \ test.txt
>Delete the c:\windows\test.txt in the windows directory
-del c: \ windows \ temp \ ?est.txt
>delete any file ending with est.txt such as west.txt or pest.pdf
RENAME or REN
-changes the name of first entered filename to the second entered filename
-if a path designation is entered for first filename, renamed file will be stored on that path
Syntax
RENAME / REN [ d: ] [ path ] filename filename
E.g.-ren a:first.txt second.txt
-change name of file FIRST.TXT on drive A to SECOND.TXT on drive A
DELTREE
-deletes a directory and all the files and subdirectories under it
-all files contained in directory or subdirectory are deleted
>regardless of attributes
Syntax
DELTREE [ /Y ] [ drive: ] path [ [ drive: ] path [ ... ] ]
Switch
/Y-Suppresses prompting to confirm you want to delete the subdirectory
E.g.
-deltree c: \ windows \ test
-deletes the test directory and everything in it
E.g.-ren a:first.txt second.txt
-change name of file FIRST.TXT on drive A to SECOND.TXT on drive A
DIR
-displays list of files, directories and subdirectories contained in current directory
>if used without an argument
-if any argument is used the contents of that directory will be displayed
Syntax
DIR [ path ] [ filename ]
-where path and filename are optional fields that specify drive, directory and / or files to list
-includes information about file sizes, date and time they were last written to
-also displays amount of space files are using
-also total amount of free disk space that available on the hard drive
E.g.-Typing dir *.txt will only list files with extension .txt.
ECHO
-repeats text typed in back to the screen
-and / or can be used to echo to a peripheral such as a COM port
Syntax
ECHO [ ON | OFF ]
-Parameters
ON | OFF
-specifies whether to turn command-echoing on or off
-to display current echo setting, use ECHO command without parameter
E.g
-Echo echo this is a test > test.bat
>this would put in the file test.bat echo this is a test, then when ever you would type in test it would type in echo this is a test<
-Echo testing the echo string
>this would type again on your screen testing the echo string then take you back to the prompt<
EDIT
MS-DOS Editor
-full-screen editor that can create, edit, save, and print ASCII text files
Syntax
EDIT [ [ drive: ] [ path ] filename ] [ /B ] [ /G ] [ /H ] [ /NOHI ]
Switches
-/B>Displays MS-DOS Editor in black and white
-/G>Uses fastest screen updating for CGA monitor
-/H>Displays max number of lines possible for monitor
MD/CD/RD
MKDIR or MD
-Used to create multilevel directory structure
Syntax
-MD [ drive: ] path or MKDIR [ drive: ] path
>Eg. MD test
-Creates test directory in current directory
CD (Change Directory) or CHDIR
-Used to switch directories
Eg.-if need to change the directory to Windows from DOS type
Syntax
-CD [ drive: ] [ path ]
>CD [ .. ]
Eg.-
-CD windows- Changing directory to Windows
-CD\ - Goes to highest level the root of drive
RD / RMDIR
-Removes empty directories in MS-DOS
>To delete directories with files or subdirectories within them must use deltree command
Syntax
-RD [ drive: ] path
Eg.-
-RD c:\ test
>Removes test directory if empty
MEM
-used to display information on>
>allocated memory areas
>free memory areas
>programs currently loaded into memory
>largest executable program size
>largest free upper memory block
>whether MS-DOS is resident in the high memory area (HMA) or not
Syntax
-MEM[/CLASSIFY|/DEBUG|/FREE|/MODULE module name]
Switches
-/CLASSIFY or /C
>Used to classify programs by memory usage
-/DEBUG or /D
>Displays status of all programs or drivers in memory
-/FREE or /F
>displays information about free memory in conventional and upper memory areas
-/MODULE or /M
>displays detailed information on memory usage of a module
>>module name is accepted as a parameter
PING
-helpful in determining TCP/IP Networks IP address
-determines connectivity issues with the network and helps resolve them
>determine if the machine being "pinged" is up and running
>>indication of delay between machines
Syntax
-ping [-t] [-a] [-n count] [-l size] [-f] [-i TTL] [-v TOS] [-r count] [-s count] [[-j host-list] | [ -k host-list]][-w timeout] destination-list
Switches
>-t Pings the specified host until stopped
-to see statistics and continue
>Control-Break
-To stop
>>Control-C
>-a
-Resolve addresses to hostnames
>>-n
-count Number of echo requests to send
>>-l size
-Send buffer size
>>-f Set
-Don't Fragment flag in packet
>>-i TTL
-Time To Live
>>-v TOS
-Type Of Service
>>-r count
-Record route for count hops
>>-s count
-Timestamp for count hops
>>-j host-list
-Loose source route along host-list
>>-k host-list
-Strict source route along host-list
>>-w timeout
-Timeout in milliseconds to wait for each reply
Eg.
-ping localhost
Or
-ping 127.0.0.1
>checks if local host (the user's machine) is up and running
>>checks that networking stack is running properly and machine is able to respond to ping request
->pinging the local host does not send information over network but helps in identifying issues with local networking stack
-ping w.x.y.z
>ping another computer where w.x.y.z indicates IP address of remote machine
->source machine sends a "PING Request" that the destination machine responds to
>time duration between request issued and response received indicates delay between machines
>>If response is not received, indicates lack of connectivity
>may be caused by cable issues, network card issues, hub issue, and so on
-determine the IP address of a remote machine by typing the domain name of the remote machine
>Eg.
1.Select Start >> click Run to open Run dialog box
2.Type command >> click OK button
3.On the command interpreter window, type:
>ping www.proprofs.com
>>first line in response indicates IP address of ProProfs.com
SET
-displays, sets, or removes MS-DOS environment variables
-often used in the AUTOEXEC.BATor CONFIG.SYS files to set environment variables each time you start MS-DOS
Syntax
-SET variable = [string]
-to display current environment settings>
SET
Eg.
-set path=c: \ windows \ command
>sets path to c: \ windows \ command
SETVER
-displays the version table
->also reports a version number (earlier than 6.0) to programs or device drivers that were designed for previous versions of MS-DOS-<
-used to display and modify version table
(version table lists names of programs and number of the MS-DOS version with which they are designed to run)
-If using a program that is not updated for a version of MS-DOS add its name to version table using SETVER
Syntax
-SETVER [drive:path]
>Display current version table
-SETVER [drive:path] filename n.nn
>Add entry
-SETVER [drive:path] filename /DELETE [/QUIET]
>Delete entry
-n.nn
>Specifies MS-DOS version to be reported
TYPE
-Displays contents of a text file
>used for viewing contents of a text file without modifying it
->read only mode
Syntax
-TYPE [ drive: ] [ path ] filename
Eg.
-type c: \ autoexec.bat
>look at contents of Autoexec.bat
/DELETE or /D
-Deletes version-table entry for specified program
/QUIET or /Q
-Hides message usually displayed during deletion of version-table entry
VER
-displays current MS-DOS version number
Syntax
-VER
Eg.
-C:\>ver
>MS-DOS Version 6.22
>>current DOS Version is 6.22
XCOPY
-Copies directories, their subdirectories, and files except hidden and system files
Syntax
-XCOPY source [ destination ] [ /Y| / -Y ] [ /A | /M ] [ /D:date ] [ /P ] [ /S ] [ /E ] [ /W ]
Switches
/Y
-Overwrites existing files without prompting
/-Y
-Prompts before overwriting existing files
/A
-Copies files with archive attribute set, doesn't change attribute
/M
-Copies files with archive attribute set, turns off archive attribute
/D:date
-copies files changed on or after specified date
>no date is given, copies only those files whose source time is newer than destination time
/P
-Prompts before creating destination file
/S
-Copies directories and sub directories excepting empty ones
/E
-Copies directories and sub directories, including empty ones
>Same as /S /E
>>May be used to modify /T
/W
-Prompts to press key before copying
Backup/Restore Utility (MSbackup, NTBackup, etc)
MSBACKUP
-Runs Microsoft Backup for MS-DOS
>backs up or restores one or more files from one disk onto another
>>can back up all files on a disk or files that have changed since last backup
->also schedule backups so they are done automatically on a regular basis, and thus restore backups
Syntax
-MSBACKUP [setup_file] [/BW | /LCD | /MDA]
>MSBACKUP program files must be located on hard disk, not floppies
NTBACKUP
-Backs-up drives / folders to tape
>available in Windows 2000 and XP
Syntax Windows 2000
-NTBACKUP backup [ systemstate ] " bks file name " / J { " job name" } [ options ] [ /um ]
>NT, Win2K and XP Pro all use NTBackup
->usually installed at setup
->>invoked through the menus, or by typing NTBACKUP on the Run line
Restoring backups created by MS-DOS 6 or 6.2 Backup programs
-MS-DOS 6.22 backup uses different backup compression format from MS-DOS 6 and 6.2. Backup
>MS-DOS 6.22 Backup program uses DriveSpace compression format
>earlier versions of used DoubleSpace compression format
->MS-DOS 6.22 Backup can't restore compressed backups created by MS-DOS 6 or 6.2 Backup
CHKDSK
-checks status of disk and displays status report
-can fix disk errors
-report shows errors found in the MS-DOS filing system, which consists of file allocation table and directories
-summary of disk usage is also displayed
-doesn't verify that information in files can be accurately read
-if errors exist on the disk, CHKDSK alerts with message
Syntax
-CHKDSK [ drive: ] [ [ path ] filename ] [ /F ] [ /V ]
Switches
/F
-Fixes errors
/V
-Displays name of each file in every directory as disk is checked
CHKDSK
-displays status of disk in current drive
DEFRAG.EXE
-rearranges files and unused space so that programs run faster
-defragment the hard disk on a regular basis for best performance
-defrag.exe is quicker and easier than going through GUI
Syntax
-defrag <volume> [ -a ] [ -f ] [ -v ] [ -? ] [ -b ]
Switches
-volume drive letter or mount point
>(d: or d:\vol\mountpoint)
1. -a Analyze only
2. -f Force de-fragmentation, even if free space is low
>Normally requires 15% of drive be free space
3. -v Verbose output
4. -? Display this help text
5. -b Defrags boot files only
Disk Cleanup Utility
-finds which files on hard drive may no longer be needed and deletes them
-using Disk Cleanup on a regular basis can significantly improve system performance
>file categories that Disk Cleanup targets
>Depending on the individual system, may or may not have all listed categories
* Downloaded Program Files
* Temporary Internet Files
* Recycle Bin
* Temporary Remote Desktop Files
* Setup Log Files
* Backup Files For Previous Operating System
* Offline Files
* Compress Old Files
-To start Disk cleanup utility
>Select Start>>Programs/All Programs >> Accessories >> System Tools >> Disk Cleanup
FDISK.EXE
-executable file provided by MS DOS and MS Windows to partition hard-disks
* Create or Delete Primary Dos Partition
* Activate or Deactivate Primary Dos Partition
* Create or Delete Extended Dos Partition
* Create or Delete Logical Drives
* Delete Non-Dos Partition
* Change Fixed Disk
Syntax
-FDISK [ /STATUS ]
Switch
-/STATUS Displays an overview of partition information of hard disk(s), without starting Fdisk program
FORMAT
-creates a new directory structure and a file allocation table
-checks for bad areas on the disk
-can delete all data that is available on the disk
-for MS-DOS to be able to use a new disk must be formated first
Syntax
1. FORMAT drive: [ /V [ :label ] ] [ /Q ] [ /U ] [ /F:size ] [ /B | /S ] [ /C ]
Eg.
1. format a
-complete format and destroys all existing data on the floppy disk
-used when the disk is not pre-formatted
2. format a: /q
-Quickly erases all data on a floppy
-does not do sector by sector scan
-used when the disk is known to be in good working condition
3. format c:
-Erases all data on hard disk
-Do not use this unless wish to erase all data
>will issue a warning before it proceeds
>>change is irreversible
->take backups of necessary files and folders in different media
ScanDisk
-full-featured disk analysis and repair program
-works on both uncompressed drives and compressed drives
Syntax
1. SCANDISK
-check the current drive for disk errors
2. SCANDISK [ drive: [ drive: ... ] | /ALL ] [ /CHECKONLY | /AUTOFIX [ /NOSAVE ] | /CUSTOM ] [ /SURFACE ] [/MONO] [ /NOSUMMARY ]
-check one or more drives for disk errors
>To check specific drive, type the drive letter after ScanDisk command
>>Eg.
-scandisk d
>SCANDISK / FRAGMENT [ drive: ] [ path ] filename
-check a file or files for fragmentation
>SCANDISK / UNDO [ undo-drive: ] [ /MONO ]
-undo repairs made previously
Computer Manager(compmgmt.msc)
-view and manage all hardware and software with device drivers console
-administer hardware devices and their drivers using Device Manager console
>further split up into the following three areas
* System Tools
o Event Viewer
o System Information
o Performance Logs and Alerts
o Shared Folders
o Device Manager
o Local Users and Groups
* Storage
o Disk Management
o Disk Defragmenter
o Logical Drives
o Removable Storage
* Services and Applications
o WMI Control
o Services
o Indexing Service
(Windows 2000 does not include Devices tool in Control Panel to start and stop device, like the one available in Microsoft Windows NT 4.0.)
Device Manager
-examine and change software-configurable devices
-check status of computer hardware and update device drivers
-use diagnostic features to resolve device conflicts, and change resource settings
-launched from the command prompt by typing devmgmt.msc
-can be used to
* Determine if hardware is working properly
* Change hardware configuration settings
* Identify device drivers that are loaded for each device and obtain information about each driver
* Change advanced settings and properties for devices
* Install updated drivers
* Disable, enable, and uninstall devices
* Reinstall previous version of drivers
* Identify device conflicts and manually configure resource settings
* Print a summary of installed devices
Event Viewer
-allows viewing of 3 types of events
* System
-Logs system errors for drivers, binding errors or service failures
* Security
-Logs logon off and log on events and other security related events as set up in event viewer
>set up in user manager
* Application
-Processes an application action creates
>Each message has an event ID number
->maximum size of logs can be set
->overriding of log entries can also be set depending on disk space
-System errors
* Information
-blue "i" represents this event
-significant event has occurred but not a critical one
* Warning
-should be checked
* Error
-must be checked
MSCONFIG.EXE
-System Configuration (MSConfig.exe) utility
>Select Start >> click Run >> type Msconfig.exe
-assists to edit and administer text configuration files like the win.ini and autoexec.bat
-important for stable and secure running of a computer and should not be terminated
-"user friendly" front end for editing system files such as win.ini and autoexec.bat
-does not exist on Windows 2000 (needs to be copied to Windows 2000)
-modify system configuration through process of elimination with check boxes
-check boxes reduce risk of typing errors associated with Notepad and System Configuration Editor
-should be logged on as an administrator or member of the Administrators group in order to change or restore settings
REGEDIT.EXE (View information/Backup registry)
-Executable file for Registry Editor used to view and change the settings in registry
-will only run while editor is open and should not be removed
-included with Windows NT 4.0 and Windows 2000 because of search capability
-can be used to make changes in Windows NT 4.0 and Windows 2000 registry
-cannot use it to view or edit all functions or data types on Windows NT 4.0 and Windows 2000
Syntax
-Export part of the Registry
>REGEDIT /E pathname “RegPath”
-Import a reg script
>REGEDIT pathname
Start the regedit GUI
REGEDT32.EXE
-Win32 version of Registry Editor for Windows NT/2000
-used for editing, deleting and inserting system registry keys
-functionality is more than regedit.exe in Windows NT/2000 system
-recommended use this program in Windows NT/2000
-breaks a string longer than 1,024 characters by inserting a null character within the string after 1,024 characters
>if a REG_MULTI_SZ value is opened that has a string that is longer than 1,024 characters and saved it then the string is broken after 1,024 characters and a null character is inserted<
-reads from the dialog box
>strings longer than 1,024 characters are truncated as EM_GETLINECOUNT and EM_LINEINDEX are being used
>>returns only the length of the first line
->Strings longer than 1,024 bytes are treated as multiple-line strings
SCANREG
-backup registry manually or allow Windows to backup the registry daily
Syntax
*SCANREG [ ? ] [ BACKUP ] [ RESTORE ] [ FIX ] [ COMMENT = "<comment>" ]
Switch
*?
-Displays usage
*BACKUP
-Backup registry and related system configuration files
*RESTORE
-Choose a backup to restore
*FIX
-Repair the registry
*COMMENT = "<comment>"
-Adds the specified comment to the CAB file while backing up
Egs.
*scanreg
-Ran alone scanreg will check registry for errors and if requested backup registry
*scanreg / restore
-Must be ran from a MS-DOS prompt and not a shell
-will allow restoration of an earlier backup of system registry
-Information on how to get to a MS-DOS prompt can be found on document: CHDOS
SYSEDIT.EXE
-text editor where SYSTEM.INI, WIN.INI, protocol.ini, CONFIG.SYS and AUTOEXEC.BAT files can be edited
-might wish to unload any extra programs that may be loading when starting computer
*C:\CONFIG.SYS and / or C:\AUTOEXEC.BAT could hold devices or programs that load and run in the background until they are needed or called for (like a screen saver, office toolbar, etc,)<
-At beginning of the WIN.INI file check 'Load=' and 'Run=' lines
>If one or both of them are there, put a “REM” comment in front of any line that is not necessary, one at a time, then try running Navigator after restarting<
>>This trial and error process helps to find out the problem that is causing the error.
->When the errors are fixed, can always remove the “REM” comments by using SYSEDIT again<-
System Monitor
-measures performance of computer or other computers on a network can be measured
*Data can be obtained in a printable graph, histogram, or report view
*System Monitor functionality can be incorporated in applications that support ActiveX controls
e.g.> Web pages, and Microsoft Word or other applications in Microsoft Office
*Create HTML pages from performance views
-browser can display views stored in HTML format
*Create reusable monitoring configurations that can be installed on other computers using Microsoft Management Console (MMC).
-start and go to run
>type perfmon.msc
>>shows System Monitor tool
->have to add counter to monitor
->>too add counters, on the Performance window, right click on the right pane, then on the popup menu click add counter
Task Manager
-NT tool for viewing system's performance
-useful in locating and isolating bottlenecks and system failures
-launched by>
*Right-click over an empty area of the Taskbar >> Select Task Manager from the popup menu, or
*Press Ctrl-Alt-Del to bring the Windows Security window and click Task Manager button
-has three tabs
1. Applications Tab
-displays a list of applications that are currently active as well as each application's status
2. Processes Tab
-lists all processes that are currently active and loaded in memory and displays several metrics or details about each one
3. Performance Tab
-displays graphs of CPU and memory usage
Edit.com
-text editor that comes with MS-DOS version 5 onwards and Windows
-Originally was just a stub that started QBasic in editor mode, but since DOS 6 it is a standalone program-
Syntax
-EDIT [d:][path]filename [/B][/G][/H][/NOHI]
>Starts the MS-DOS editor used to create and edit ASCII text files
-full-screen text editor
-includes pull-down menus
-has options for creating, editing, saving, and printing ASCII files
-includes extensive online Help
EXTRACT.EXE
-takes files that are compressed together in a Windows Cabinet file format (.cab extension) and gets individual files that constitute the compressed file-
Syntax
*EXTRACT [ /Y ] [ /A ] [ /D | /E ] [ /L dir ] cabinet [ filename ... ]
*EXTRACT [ /Y ] source [ newname ]
*EXTRACT [ /Y ] /C source destination
*cabinet
-Cabinet file (contains two or more files)
*filename
-Name of the file to extract from the cabinet
-Wild cards and multiple filenames (separated by blanks) may be used
*source
-Compressed file (a cabinet with only one file)
*newname
-New filename to give the extracted file
-if not supplied, original name is used
Switches
/A
-Process ALL cabinets
-Follows cabinet chain starting in first cabinet mentioned
/C
-Copy source file to destination
-to copy from DMF disks
/D
-Display cabinet directory
-use with filename to avoid extract).
/E
-Extract
-use instead of *.* to extract all files
/L dir
-location to place extracted files
-default is current directory
/Y
-Do not prompt before overwriting existing file
Windows Explorer
-component of the Windows operating system that enables control of computer
-replacement to the older Windows file manager
-performs following operations
*Finding Files
*Saving Files
*Copying Files
*Moving Files
*Deleting Files
*Creating Folder Directories
Posted by cherrycat, Jun 27 2007, 11:31 AM
SYSTEM FILES AND PARTIONS
Windows-9x System Files
* Windows 95
1. Windows 95 OEM
2. Windows 95 OSR
3. Windows 95 OSR
4. Windows 95 OSR 2.1
* Windows 98 series
1. Win98 standard
2. Win98 upgrade
3. Win98 Second Edition
IO.SYS
>hidden system file in root directory of primary partition of primary drive
>essential part of DOS and Windows 9x
>defines basic input / output (I / O) capabilities
->helps in communicating with peripherals
<>boot sector loads the IO.SYS
->IO.SYS loads the next system file, MSDOS.SYS.
>Windows 9x and DOS operating systems rely on hardware interfacing routines
->IO.SYS loads these routines before loading MSDOS.SYS
>IO.SYS manages the overall loading of the Operating System.MSDOS.SYS
MSDOS.SYS
>hidden, system, read-only, text configuration file
->not an executable program
>in the root directory of boot drive
>contains paths that have information about location for other Windows files like Registry
>file determines whether the computer boots into DOS or into Windows 95/98
>in DOS, works with IO.SYS to start boot process
>in Windows 9x, is a configuration-based file
AUTOEXEC.BAT (EXECUTED BY COMMAND.COM->WHICH IS LOADED BY IO.SYS)
>system file executed automatically when system starts
>used in DOS and early versions of Windows to run other programs listed in file
->e.g. c:\windows\win runs Windows 3.x automatically when computer boots
COMMAND.COM
>executes all commands before loading and initializing Windows kernel
>loaded by IO.SYS and executes AUTOEXEC.BAT before it loads kernel
->contains all the internal dos commands
->>dir, mkdir, type, cls, etc.
CONFIG.SYS
>file that instructs OS to setup computer
>user-configurable file
->contains device drivers and system setup configuration
->>specifies memory for device drivers and programs that control hardware devices
>enables or disables system features
>sets limits on system resources
HIMEM.SYS
>memory management utility
->manages memory so that two applications or device drivers don't use same memory locations at same time
>installed by adding <DEVICE> command for HIMEM.SYS to CONFIG.SYS file
->HIMEM.SYS command line should precede any command to start applications or device drivers that use extended memory
EMM386.SYS
>extended memory manager
>Without an extended memory manager computer would only able to use basic 640KB
<>Syntax:
-Device=Emm386[options][Parameters](for Config.sys only)
-EMM386.exe=[options][Parameters](for autoexec only)
WIN.COM
>contains user and program settings
>required for backward compatibility with 16 bit applications
>error message may occur on start-up and return the system to MS-DOS prompt
1. The following file is missing or corrupted: Win.com.
2. The following file is missing or corrupted: Win.com Program too big to load in the memory.
3. Cannot find Win.com, unable to continue loading, Windows Program too large.
>means the Win.com file is missing or damaged
SYSTEM.INI
>System Initialization File
>contains information about computer's hardware settings
>file must be placed in Windows folder
->loads the sound, video and mouse drivers
>contains drivers for a 16-bit system
>to edit SYSTEM.INI use SysEdit.exe
->can be used with all versions of Windows 9x
>not used widely in later versions as compared to Windows 3x
->useful to load 16-bit MS-DOS real-mode drivers
>If missing or corrupted, Windows 9x will create a new one and start loading settings again
WIN.INI
>located in windows directory
>loads all the system settings every time system boots
->every time system reboots, WIN.INI is initialized
->>communications drivers, wallpaper, screen saver, languages, fonts and such are loaded
>If corrupt, Windows will not load, or will show errors while loading
->program has to be reinstalled
SYSTEM.DAT
>Registry is managed by two files
* SYSTEM.DAT
* USER.DAT
SYSTEM.DAT
>contains all hardware configurations, plug and play settings, application settings
->hidden file in root or c:\windows.
>All information displayed in HKEY_LOCAL_MACHINE within Registry is stored in SYSTEM.DAT
>system takes a back up on boot up
Registry Data Files
>located in c:\windows directory
>contains
* Logon names
* Desktop settings
* Start menu settings
>HKEY_CURRENT_USER stores user specific settings
->stored as USER.DAT in Windows directory
Windows NT-based Specific Files
Windows NT/2000 Structure
>boot files used by Windows NT and 2000-
*BOOT.INI- contains boot defaults, OS locations, settings and menus
*BOOTSECT.DOS- provides option to boot other OS
*NTDETECT.COM- detects hardware
>located at root of system partition or C:\.
*NTLDR- loads OS
>located at root of system partition
*NTOSKRNL.EXE- The executable file
*HAL.DLL- Hardware abstraction layer
*OSLOADER.EXE- OS loader for RISC based systems
*NTBOOTDD.SYS- helpful when system or boot partition is on a SCSI drive or a removable media such as external drive and when BIOS is disabled
BOOT.INI
>in root directory of primary boot partition
>holds the menu for available operating systems
>two parts BOOT.INI
* Boot loader
* Operating systems
Example of BOOT.INI
[boot loader]
timeout = 30
default = multi(0) disk(0) rdisk(0) partition(2) \ WINDOWS
[operating systems]
multi(0) disk(0) rdisk(0) partition(2) \ WINDOWS = "Microsoft Windows XP Professional" / fastdetect
C: \ bootsect.dos = "Microsoft Windows 98"
1.Boot loader
>two parts Timeout and default
1.Timeout- time given to make choice of booting OS other than default
2.Default- has path of default OS
>if choice is not made within specified time the default is loaded
2. Operating System
>lists all available OSs and their paths
1. SCSI (n) or multi (n)
>SCSI option used for SCSI adapters not enabled in BIOS by default
>Multi (n) used for all other types of HDs
>variable n indicates number of adapters
2. Disk (n)
>If multi option is used then is 0 and if SCSI is used then is the bus number of SCSI
3. rdisk (n)
>If SCSI is used then n is 0.
>If IDE is used then primary is 0 and secondary is 1
4. Partition (n)
>partition with the system files
->starts from 1 not 0
5. \path
>directory where system files are located
->default path is \winnt
NTLDR
>file responsible for booting OS from storage devices like CD-ROM, USB etc
>helps in booting non-Windows based OS
>has two parts
*first part contains->
>boot loader itself and the second part contains->
>BOOT.INI, which contains configuration options for boot menu
>NTLDR needs NTDETECT.COM to boot NT based operating system
>When booting OS NTLDR performs following actions
1. first places processor in flat 32-bit mode
2. then accesses file system on primary drive or boot drive
3. reads contents of BOOT.INI file and prompts user with OS menu
4. if OS other than windows exists then reads configuration from BOOT.INI
>loads BOOTSECT.DOS and then passes control to it
5. If Windows NT based OS then NTLDR loads NTDETECT.COM
>NDETECT.COM collects information about hardware
6. NTLDR runs NTOSKRNL.EXE with information returned by NTDETECT.COM
NTDETECT.COM
>read-only hidden system file
>resides in root of primary partition
>responsible for examining hardware and building list
->then passes list to NTLDR to build hardware list in registry key HKEY_LOCAL_MACHINE
>Windows 2000 has advanced file called INSTALLD.CMD that contains debugging features which is also checked version of ntdetect.com<
>contains information about system components like bus and adapter components, disk geometry, read-only memory (ROM) blocks, keyboard and communications (COM) port and parallel port components, mouse component, and floppy disk drive component<
NTBOOTDD.SYS
NTBOOTDD.SYS
>device driver file will only be used on systems that boot from a SCSI disk on which SCSI adapter BIOS is disabled
>used to recognize and load SCSI interface
> without SCSI device not required and is not installed
NTUSER.DAT
>contains information about user's profiles and configurations
>has copy of Windows NT registry in HKEY_CURRENT_USER sub-tree
>HKEY_CURRENT_USER contains configuration information of current user
Registry data files
>registry is central repository of system and hardware configuration
>data is stored in a structured hierarchy of keys, sub-keys, and named values
->are referred to as hives
>registry data in Windows 95, 98 and ME stored in-
* SYSTEM.DAT
* USER.DAT
* POLICY.POL
Windows NT,2000 and XP>
* Security
* System
* Default
* Sam
* Software
* System.dat
* Ntuser.dat
>access registry by clicking on start>>run. Type 'regedit 'in open box and press the return/enter
>always backup the registry before making changes
Disk Partitions
>new hard drive needs to be partitioned and formated
>Partitioning is creating logical divisions on hard disk
->allows installation of an OS
->>manage data on the computer
->>install multiple OSs in logical partitions
Advantages
1. Limitations of the operating system's file system (example some Microsoft operating system's support only FAT16 and others support NTFS or FAT32).
2.one partition is bad or the file system looses integrity only that partition is affected
3. multiple OSs in different partitions
4. store files in different partition and OS files in another
5. increases read-write speed
6. customize each partition per need
DOS
-two types of partitions
>primary partition and extended partition
-primary is first partition created is the physical disk
>drive name assigned always C
-other partition created after this are extended partitions
>logical drives exist in extended partitions
->assigned drive letters from D-Z
FDISK
-located in the boot disk
>run to create partitions
-With a new disk then you first boot from a bootable floppy or CD
>at the DOS prompt type FDISK, then press the return/enter key
Primary Partition
-run FDISK
*Select option 1 (create DOS primary or logical drive)
*On second menu page select 1 to create primary partition
-on next page FDISK will show total disk space available for the HD
-choose to use entire HD for primary partition or a percentage of HD
*FDISK examines HD and creates primary partition
Active Partition
-after primary partition is created make active partition to tell DOS that OS resides on this drive
>can also make any logical drive as an active partition
->must create an active partition so DOS will know where OS files are
>Normally Primary DOS partition is the active partition
1. run FDISK
2. Select option 1, create a primary DOS or logical drive
3. On second screen select option 2, create active partition
4. FDISK will display all partitions
-select primary partition to make it active
5. Exit FDISK
Extended Partition
-extended DOS partition holds all logical partitions
>Extended DOS partition does not hold Primary DOS partition
->DOS supports only 4 primary partitions and 24 extended partitions to be created
->>recommended only make 12 extended partitions because performance of HD can go bad
1. run FDISK
2. Select option 1 on the first screen
3. Select option 2 on the second screen
4. Define the disk space
5. it will warn there is no logical drive, so one must be created
Logical Drive
-no limit on the number of logical partitions
1. run FDISK
2. Select option 1 on the first screen
3. Select option 2 on the second screen
4. Define the disk space
5. warning stating that no logical drive is defined
6. next screen asks to create logical drive
-either specify disk percentage or size of partition
7. FDISK examines the disk and creates the logical drive and allots a drive name
8. FDISK will go back to screen where the logical drive was made
-choose to make more logical drives or exit FDISK
<>must format all logical drives before use
File System
-defines how the files and folders are organized
-specifies how data is read or written to storage devices
-Most make use of sectors
>length of each sector is 512 bytes
-FS specifies how it organizes files and directories in sectors
-keeps track of which sector is not used and which ones are used
-DOS based system and Windows 9x OS use FAT file systems
>File Allocation table
->contains an index file that stores the location of all file and directories
->>requests for read or write first accesses Index file for the location of the file
common File Systems used by Windows
* FAT 16
* FAT 32
* NTFS 4
* NTFS 5
FAT16
-designed for MS-DOS
-can read and write 16 bits of information at a time or 1 cycle
-found in Windows 95/98/ME and Windows NT
Properties
*maximum partition size of 2.1 GB in MS-DOS
-4.0 GB under Windows NT
*maximum files of 65,536
*Restricted to 512 entries in the root directory of HD
-128 entries in the root partition of a floppy disk
*No support for long file names
Advantages
*Compatible with other operating systems like Windows 95/98 and NT.
*No Size Overhead.
Disadvantages
*Large cluster size results in poor use of drive space for large partitions
*No compression available under Windows NT
*Minimal security
-may only set read only and hidden attributes of files
*Updating FAT table is slow
-performance decreases as partition sizes become greater than a few hundred MB
FAT32
-capable of reading and writing 32 bits of information at a time
>maximum partition size of 2048 MB
-can support a maximum of 2,097,152 files(per partion)
-restricted to 65,535 entries in root directory of HD
-supports long file names
Advantages
*Small cluster size of 4K
*Re-locatable root directory
-allows for greater number of entries
*file allocation table (FAT) and master boot record (MBR) can be relocated
*Backup copies of FAT and MBR can be created with the use of proper tool
*can disable writing to the secondary FAT
-can run direct read from the secondary FAT if the primary FAT lies on a bad cluster
Disadvantages
*Size overhead
-best used with larger HD
*Not compatible with many disk utilities
NTFS 4
-evolved from HTPS
>HTPS created by OS/2
-partition size of 16 GB
>C2 level security and long file names
Advantages
*Small cluster size
*Performance does not degrade as partition size increases
*Compression and encryption
*Disk quota.
*Security.
*Automatic bad cluster re-mapping.
*Little need for drive repair utilities(??)
Disadvantages
*Only compatible with Windows NT, 2000, or XP
*Large overhead
-no drives that are smaller than 400 MB
*Not possible to format removable diskette (floppy/Zip drive/CD-R) with the NTFS file system
NTFS 5
-launched with Windows 2000
-added features like Active Directory Support
>all features of NTFS 4 with support for encryption of data at volume, directory or file level
-new features of NTFS 5
*File/directory encryption
*Per-user, per-volume disk quotas
*Hierarchical Storage Management (reparse points)
*Mount points
*Distributed link tracking support
*Sparse-file support
*Volume change tracking
*Encryption.
Directory Structures
-directory holds subdirectories and files
>itself is a file
->has a special structure about that contains the links to point to the data in the file
-directory structure looks like a hierarchical tree structure
>entries in the directory are 32 bytes in length
directory stores information such as-
1.File name and Extensions
-dependent upon the OS being used
-e.g. DOS 8.0 directory structure supports 11 characters for file names
2.File Attribute byte
-inform if the file is a real file or a subdirectory
-several types of file attributes that an OS supports
3. Last change / Date and time
-tells about the date and time of file created and who the owner of the file is
-Every time this file is accessed the last modified time changes to the current time.
4. File Size
-size of the file in bytes
5.Link to Starting Cluster
-defines starting location of file if file is stored in multiple locations on hard disk
Create Folders
-CLI use command 'md'
-MD stands for Make Directory.
-Name folder anything you wish
-GUI
clicking or choose from menu
e.g. making folder on C Drive
Double -click with the mouse on My Computer icon or right click on icon and left click on open
1. My Computer shows primary and logical drives and removable media drives
2. Open the C drive by double-clicking it
3. all the folders and files in C drive are visible
-Right click in window and select New and then select Folder
4. new folder will be displayed with name called New Folder
5. Type the name of the folder
Navigate the Directory Structure
-GUI based can see the icons for folders and file
>just need to know location of directory
-open My Computer
>select the drive
->open it
-shows list of all folders and files
->select the folder or file
-DOS based operating systems
-CD command to change or navigate through the directory
>CD means Change Directory
->CD <name of the directory>
->>e.g. use CD\ to go the root directory
Maximum Depth
-some file systems have hierarchical directory structure and have unlimited depth
-Some have a limit on the depth of the directory structure
-in most File systems directory structure is fixed and read-only
>can create directories or folders and file, and perform operations like modifying and deleting directory or folder inside directory or folder<
->FS will not allow modification of structure of directory or folder
Files
-can be defined as stream of bits stored as single unit in storage unit like the HD
-the single stream can be stored as multiple fragments of data in multiple locations
-managed by the OS
-OS creates files in format supported by FS
>always assigns names so that it can be referred later
Creating files
-GUI based
1. decide where to create the file
-which drive and under which folder
-can create files on desktop and in my documents
2. eg. To creat on desktop right-click on the desktop and select New
-click on the type of file to be created
-create files in the same way in other folders
3. select type of new file, windows will display new file with the default file name as new file
-give your own file name here and then press enter.
File Naming Conventions
-rules are specific to the File system
>DOS (e.g) supports 11 characters long file names
->Eight bits are reserved for name of the file
->>3 bits for file extension
-extension of the file associates the file with type of application
>e.g. file1.txt is a text file Here .txt identifies the file as text file
-Windows supports long file names
-cannot use characters like ", *, <, >, :, ?, /, \, " while creating the files
-need not specify the file extension in windows
>windows will make you choose the type of file from the available list
-identify files by looking extensions
File Attributes - Read only, Hidden, System and archive
-define characteristics of file
-define how file is to be used
-can assign multiple attributes to a single file
-stored in a byte in directory structure
-DOS
>set attributes by using attrib command
-Windows
>set attributes by going to properties of the file
->right click the file and select properties
*Read-only
=software that is operating the file will refuse to delete or modify it.
*Hidden
-will not see file under normal operation
->in Windows all critical files will be hidden
*System
-marks a file as system file
>System files should not be modified or deleted
*Volume Label
-logical disks can be assigned a name
*Directory
-differentiates files as directories or files
*Archive
-every time the user or the software modifies a file, the archive bit will be marked
>tells you when file was last modified
File Compression
-compressing the file to reduce overall size of the file
-many types of algorithms and utilities are available to perform compression
-carried out by mathematical functions
-uncompress the file to original contents
-helps put more data in storage devices like floppy and ZIP drives
-takes less bandwidth to send it over internet as it takes less time to send the file
-use utilities like Win zip to compress and uncompress files
File Encryption
-an algorithm that encodes plain text into non-readable form or cipher text
>receiver of the encrypted text uses a "key" to decrypt the message
-basically designed for military purpose with the aim of safe guarding critical data from enemies
>Now used by many others
-classified strong or weak based on the size of encryption bit
File Permission
-protect files from unauthorized or malicious users accessing or deleting them
-three basic file permission available for a file
1. Read
-Allows you to read the file
2. Write
-Allows you to read and write to file
3. Execute
-Allows you to execute the file
-set as needed to the user of a file
-owner of the file has full access to the file
-owner is responsible for providing file permission to user
-when user logs in and tries to access the file he will be checked against the permissions set by owner
Text Files
-refer to strict ASCII
-do not need special software to view them
-extension of .txt by default
Binary Files
-can be practically anything
-All files on a computer are binary in the strictest sense
-can be compiled executable code, object code or libraries, images, media such as audio or video, ZIP archives
Posted by cherrycat, Jun 23 2007, 01:17 PM
Windows
Windows>most commonly used operating system
>released by Microsoft
>runs server machines as well
>various versions suitable for different types of configurations.
*Windows 95
*Windows 98
*Windows Me
*Windows NT 4.0 Workstation
*Windows 2000 Professional
*Windows XP
1. Windows 95
>hybrid 16-bit/32-bit graphical OS
>"Start" button and "Taskbar" first started here
>featured significant improvements to graphical user interface (GUI)
a. Desktop
b. Start Menu
c. support for 256-character mixed-case long filenames
d. preemptively-multitasked protected-mode 32-bit applications
>introduced FAT32
>does not support older, 16-bit x86 processors
>required an Intel 80386 (or compatible) processor
>new features of Windows 95
*Desktop
*Right Button Menu
*Taskbar and Start Menu
*Built-in Network Support with Dial-up for different protocols
*Enhanced Help System
*Folder view of files and resources
*Support of 32 bit application, pre-emptive multitasking and thread
In old Windows, user interface depended on programs menus
>in Windows 95, user was able to save and open from desktop
2. Windows 98
>hybrid 16-bit/32-bit GUI OS
a. included the Internet Explorer 4 browser
b. not many other changes between the two.
>a bit slower when compared to Windows 95
>had many stability and compatibility issues
>>Windows 98 Second Edition (Windows 98 SE) released in 1999
>included fixes for many small issues
>>replaced Internet Explorer 4 with faster and lighter IE5
>>added Internet Connection Sharing
a. allowed two computers on a LAN to share a single Internet connection through NAT
>Netmeeting 3
>support for DVD
Key New Features
*Improved new looking Windows (user interface)
*button for switching to desktop "Show Desktop" was placed on quick launch tool bar
*Integrated Microsoft Internet Explorer in Windows Explorer and Help System
*improved to support more hardware
Added
*Personal Web Server
>supports Common Gateway Interface (CGI) and Internet Server Application Programming Interface (ISAPI) applications
> could be used for staging server to test Web applications before using them on real-time server
*faster Shutdown
3. Windows Me
>Windows Millennium Edition, released in 2000
>>32-bit graphical OS
>created for home users
>bundled with Windows Media Player 7
>includes small upgrades
a. Internet Explorer 5.5
b. new Movie Maker software
>provided basic video editing
>designed to be easy for home users
c. introduced "System Restore" logging and reversion system
Key New Features
*New media player which supports more file types, with changeable skins
*New high-color system icons
>interface is similar to Windows 98 and Windows 2000
4. Windows NT 4.0 Workstation
>Windows NT "New Technology" 4.0 released in 1996
>>32-bit Windows OS
>available in workstation and server versions with a GUI similar to Windows 95
>more stable than Windows 95
>less flexible from a desktop perspective
>>many programs written for the Win32 API will run on both Windows 95 and Windows NT
>majority of 3D games won't
A. different packages of Windows NT 4.0
*Windows NT 4.0 Terminal Server
a. allows remote log on
*Windows NT 4.0 Enterprise Server
a. designed for high-demand, high-traffic networks
*Windows NT 4.0 Server
a. designed for small-scale Business Server systems
*Windows NT Workstation
a. designed for use as general business desktop OS
>has the look and feel of Windows 95
>>completely different OS
>interface includes
*Start Button, Taskbar, Shortcuts
*My Computer, Network Neighborhood, and the Recycle Bin
>advanced security features
>advanced network support
>Full 32-bit operating system
>advanced multitasking, user administration, client-server architecture
>>lacked the support of drivers, features, and gaming support compared to Windows 95 / Windows 98
5. Windows 2000
>also known as Windows NT 5.0
>32-bit preemptible , interruptible graphical business-oriented OS
Versions
for desktops and servers
*Professional
*Server
*Advanced Server
*Data Center Server
>interface remained almost the same
>integrated IE5.
main advantages
*Stability
a. keeps running even if a program crashes or locks up, other programs won't be affected
*Intelligence
a. cannot run out of resources
1. no lockups and crashes as were common to Windows 95, 98 and Me
*Security
a. Standard log-on password used in Windows 2000 cannot be hacked
1.others need to be authorized to use it.
*Integrity
a. prevents any program you are installing from damaging files that Windows requires
b. prevents anything happening to files other programs are using
*Familiarity
a.same look and feel of Windows 95, 98 and Me
6. Windows XP
>Windows XP "Experience"
>also known as Windows NT 5.1
1. Windows XP Home Edition targeted at home users
2.Windows XP Professional
a. Security Center
>allows checking of the status of important security elements -Windows Firewall, Automatic Updates, and virus protection software.
>improved performance over previous versions and allows running more programs at the same time
>Windows 95/98, and Windows Me were designed for home based desktop PCs
>>lacked reliable memory protection
>XP is an evolution of Windows 2000 with additional features for home users
Windows XP Professional additional features(over Home)
*Win XP pro has remote desktop host and client. Win XP has home remote desktop client only
*Centralized administration features
a. Roaming User Profiles
b. Group Policies
c. Automatic Software Installation and Maintenance
d. Remote Installation Service (RIS)
*Encrypting File System (EFS)
a. encrypts the files in the hard drive so that they cannot be read by another user
*Offline Files and Folders
a. allows a PC to automatically save a copy of files from other networked computer and work with them while disconnected from the network
*Symmetric multiprocessing
a. ability to divide tasks between multiple CPUs
1. XP Pro can support two CPUs
*XP will not allow user to set a resolution lower than 800*600
Registry
OS-defined database
>stores all information and settings of all hardware, software, users and preferences. Essential to the computer.
>for 32-bit Microsoft OS only
*Any changes made in control panel setting, adding a sound card, file allocation or the installation and removal of 32-bit software are stored there
*stored in several hidden files, depending upon the versions of Windows
*can be edited by executing the command "regedit.exe"
a. type start run
b. type regedit.exe in dialog box
c. press enter key or click Ok
d. Opens More Info in a new browser window
>Windows 3.1 also has a registry
>less important to the functioning of the OS
Registry Structure
>grouped in a hierarchical structure of sub-trees and sub-keys, and entries
>registry contents of one computer may differ from that of another
>hive is a discrete body of keys, subkeys, and values rooted at the top of the registry hierarchy
a. most information in the registry is stored on disk and is considered permanent
b. some information, stored in volatile keys, is overwritten each time the OS starts
Registry sub-trees
>Windows Server 2003 group of OSs has two sub-tree registries
a. HKEY_LOCAL_MACHINE
b.HKEY_USERS
-Registry Editor utilities display five sub-trees, three of which are aliases of other parts of the registry.
five sub-trees
1.HKEY_CLASSES_ROOT
a. Contains information needed by various file-class association data and OLE technologies
>corresponding key or value exists in either HKEY_LOCAL_MACHINE\SOFTWARE\Classes or HKEY_CURRENT_USER\SOFTWARE\Classes if a particular key or value exists in HKEY_CLASSES_ROOT<
>If a key or value exists in both places, HKEY_CURRENT_USER version is the one that appears in HKEY_CLASSES_ROOT
2. HKEY_CURRENT_USER
a. Contains user profile for the current logged in user
>includes environment variables
a. network connections
b. desktop settings
c. printers
d. program preferences
>is an alias of the HKEY_USERS sub-tree
>points to HKEY_USERS\security ID of current user
3. HKEY_LOCAL_MACHINE
a. contains information of the local computer system
>hardware and operating system information such as bus type, device drivers, system memory, and startup control data.
4. HKEY_USERS
a. contains information of the default profile and the actively loaded user profiles
>includes information that also appears in HKEY_CURRENT_USER
>remote users do not have profiles under this key on the server
->their profiles are loaded into the registry of their computers
5.HKEY_CURRENT_CONFIG
a. Contains information of the hardware profile used by the local computer system at startup
>used to configure settings like loading of device drivers and display resolution to use
>part of the HKEY_LOCAL_MACHINE sub-tree and points to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Hardware Profiles\Current.
>each root key name begins with HKEY_ to indicate to software developers that this is a handle that a program can use. A handle is a value used to identify a resource so that a program can access it<
Data types currently defined and used by the system
*REG_BINARY
a. most of the information of hardware components are stored as binary data and displayed in Registry Editor in hexadecimal format
*REG_DWORD
a. data represented as a 4 bytes long number
>most parameters for device drivers and services are of this kind and are displayed in Registry Editor in binary, hexadecimal, or decimal format<
*REG_EXPAND_SZ
a. variable-length data string which includes variables that are resolved when program or service uses the data
*REG_MULTI_SZ
a. multiple string
>values that contain lists or multiple values in a form that can be read are usually this type
->entries are separated by commas, spaces, or other characters
*REG_SZ
>fixed-length text string.
*REG_FULL_RESOURCE_DESCRIPTOR
>series of nested arrays which stores a resource list for a hardware component or driver
Entries in the registry keys
>data that can be contained in a registry key or sub key are called as entries
>some store specific user information
>others store information of all the users of a computer
3 parts
1. the name of the value,
2. data type of the value
3. the value itself
Backup and Restoration
Windows 95
<Configuration Backup program
a. cfgback.exe
>allows creating up to nine different backup copies of the Registry
->stored with the extension RBK, in the \Windows directory
>if system is set up for multiple users, cfgback.exe won't back up the user.dat file
Windows 98
>automatically creates a registry backup copy every time it starts
>can manually create a backup using the Registry Checker utility by running scanregw.exe from Start >> Run menu.
Windows NT
>use either the “Last Known Good configuration” option or RDISK
>at least during the installation most Windows applications write data to the Registry
>can be edited directly by using the Registry Editor (regedit.exe)
>great care must be taken while dealing with registry because errors in it could disable the computer
Virtual Memory
>allows users to utilize a very large range of memory or storage addresses for stored data
>system maps the user's virtual addresses to real hardware storage addresses
>when all physical memory is being used, system can simulate more memory by using empty sectors in the hard drive to store additional data<
>known as swapping
a. hard drive access times are much slower than memory access times
>virtual memory can decrease the performance severely
>permits software to use more main memory than the actual physical memory
->programs could have access to 4 gigabytes of virtual memory on a computer's hard drive, even if the computer has only 32 MB of RAM<-
four kinds of memory
1. registers in the CPU
2. caches both inside and adjacent to CPU
3. physical memory(RAM) which the CPU can write and read to directly and quickly
4. disk storage, which is much larger, but also much slower
>applications require access to more information than can be stored in physical memory
>especially true when the OS allows multiple processes/applications to run seemingly in parallel
>applications cam keep some information on the disk, and move it back and forth to physical memory as needed
Basic operation
>When memory is used, by the CPU, either virtual or main ,hardware translates the address of the memory location generated by the software (the virtual memory address) into either-
*address of a real memory location (the physical memory address),( memory reference operation is completed, just as if the virtual memory were not involved) or
*an indication that the desired memory item is not currently resident in main memory (a so-called virtual memory exception)
>the OS is invoked to handle the situation
->actions needed before the program can continue are quite complex
>hardware that supports virtual memory usually supports memory protection mechanisms
Paging and virtual memory
>Virtual memory usually implemented by paging
->low order bits of the binary representation of the virtual address are preserved, and used directly
->>low order bits of the actual physical address
->>high order bits are treated as a key to one or more address translation tables
->>>provide the high order bits of the actual physical address
>range of consecutive addresses in the virtual address space whose size is a power of two will be translated in a corresponding range of consecutive physical addresses<
>memory referenced by such a range is called a page
>page size usually in the range of 512 to 8192 bytes
>The OS stores the address translation tables, the mappings from virtual to physical page numbers in a data structure known as a page table<
>if page is marked as unavailable and CPU tries to reference a memory location in that page, the MMU responds by raising an exception generally called as page fault with the CPU, which then jumps to a routine in the operating system. If the page is in the swap area, this routine invokes an operation called a page swap to bring in the required page<
>Windows automatically sets the page file to be 1.5 x physical memory
>memory intensive applications on a low physical memory system, might need more
>fixing the size of the swap file will prevent it from being dynamically resized by Windows
>resizing causes the swap file to become fragmented, resulting in reduced performance.
Files
>file is a collection of information, such as text, data or images saved on a storage medium like a hard disk
File systems
>file system is the way in which an OS manages a set of hierarchical files
->defines how files are named and where they are placed logically for storage and retrieval on storage devices
>journaling file system provides quick recovery time by logging the file system metadata
>Data integrity is ensured because updates to files' metadata are written to a serial log on disk before the original disk blocks are updated<
Aspects of file systems
>underlying data storage device offers access to an array of fixed-size blocks
->sectors, generally 512 bytes each
>file system software organizes sectors into files and directories
>keeps track of which sectors belong to which file and which are not being used
Types of file systems
1. Disk file systems
a. designed for the storage of files on a data storage device
>directly or indirectly connected to the computer
>Eg.
->FAT, NTFS, ext2, ISO 9660 and ODS-5
A. FAT
>resides on a data storage device
->indicates status and location of all data clusters that are on the device
>file allocation table is like a "table of contents" of a memory card
->if file allocation table is damaged or lost, card is unreadable
>highest-level logical disk structures are the master boot record and partition tables
->define the way the entire disk is sized and organized
B. Network file systems
>also known as a distributed file system or DFS
>files are accessed over a network
->> possibly simultaneously by several computers
>ideally, access to network file systems is user transparent
>EG.
->NFS, CIFS, Lustre, and Global File System
>primary functions of NFS are to export or mount directories to other machines
>can then be accessed as though they were local
>uses a client / server architecture
->consists of a client program, a server program, and a protocol used to communicate between them
>server program makes file systems available for access by other machines via exporting
->shared file systems.
C. Database file systems
>instead of hierarchical structured management, files are identified by their characteristics, like type of file, topic, author, or similar metadata
>file search can be formulated in SQL or in natural speech
File systems and OSs
>file systems are an integral part of any modern OS
>early OSs had a separate component for handling file systems
->disk operating system
>On some microcomputers, the disk OS was loaded separately from the rest of the OS
>interfaces can be textual or graphical
File systems under Windows
>File Allocation Table and NTFS
>Older versions of the FAT file system had file name length limits
->restrictions on the maximum size of FAT-formatted disks or partitions
>NTFS
->introduced with Windows NT
>allowed ACL-based permission control
>Hard links, multiple file streams, attribute indexing, quota tracking, compression and mount-points for other file systems are also supported, though not all well-documented<
>Windows uses a GUI
->directories are folders which contains files
->>represented graphically with a folder icon
Windows Explorer
>used Windows for displaying file and directory listings and information
>originally was distinct from Internet Explorer
>debuted in Windows 95
>Besides file management deals with functions tied to the Windows "Start" menu (Run, Settings, Documents and so on)
>in XP, Windows Explorer is different than in previous Windows versions
->>Luna interface is used but can be turned off if desired
>option to provide thumb view of graphic files, and rendering of HTML-files including graphic files and other HTML-files referred to<
can be done
*one-by-one, in a detail panel showing details about a selected file
>in Windows 98 a HTML-file can be edited to customize the detail panel
*of all files in a folder, with the view-miniatures setting
*within a folder pictogram, of up to four files in that folder
>Windows 95 supported two modes of folder browsing
a. opening a new folder in a new window
b. opening a new folder in the same window
>set in the Folder Options dialog box
Windows 2000
>folder browsing windows still automatically resize
>usually a little bit too small status bar is visible
>"List" view is not automatically applied to file-plenty folders
Windows XP
>doesn't resize the window
My Computer
>represents a user's private, usually local, storage
>source of all information about computer resources including the drivers and control panel
>shows the contents of floppy disk, hard disk, CD-ROM drive, and network drives
In XP it is the icon in the start menu
>all other versions icon on the desktop
>Windows 98 includes the printing mechanism and dial-up networking mechanism
>displays local resources
>remote resources are displayed with Network Neighborhood
->EXCEPT Windows XP
->>My computer of Windows XP displays both local and remote resources
Control Panel
>a tool used to change the settings in the OS or computer
>change the hardware settings like keyboard and mouse sensitivity, speaker volume, display colors and resolution as well as modem, network and printer settings<
>part of the Windows GUI menu accessible from the Start Menu
>>view and manipulate basic system settings and controls, such as adding hardware, adding/removing software, controlling user accounts, changing accessibility options etc<<
*click Start>Control Panel
**Classic view click Start, point to Settings, and then click Control Panel
Accessibility Options
>configure the accessibility
>primarily aimed at users with disabilities or hardware problems
*keyboard can be modified
>difficulty pressing key-combinations, or pressing a key just once
*Behavior of sounds
*contrast of the system can be changed
*mouse functions can be made to work with the keyboard
Add Hardware
>wizard which allows users to add new hardware devices to the system
>selecting from a list of devices or specify location of driver installation files
Add/Remove Programs
>add or remove programs from system
>also displays how often the program is used and how much disk space it occupies
Administrative Tools
>various tools for system administration, including security, performance and service configuration
Date and Time
>change the date and time stored in BIOS, change time zone and synchronize date and time with internet time server
Display
>Display Properties allows alteration of display settings of computer such as desktop background, screensaver, display resolution etc.
Folder Options
>configuration of how folders and files are shown in Windows Explorer
>modify file type associations in Windows
->which program opens what file types
Fonts
>shows all fonts installed on the computer
>remove fonts, install new fonts or search for fonts using font characteristics
Game Controllers
>view and edit game controllers
Internet Options
>change internet security settings, internet privacy settings, HTML display options and various browser settings like homepage and plug-ins<
Keyboard
>change and test keyboard settings, including cursor blink rate and key repeat rate
Mail
>configure mail client in Windows, usually Microsoft Outlook
>>Microsoft Outlook Express configured through own interface
Network Connections
>edit or create network connections such as Local Area Networks (LAN) and internet connection
>troubleshooting functions in case computer has to be reconnected to network
Phone and Modem
>telephone and modem connections
Power Options
>manage energy consumption
>decide what to do when the computer's on/off button is pressed and whether or not to activate sleep mode.
Printers and Faxes
> shows all printers and faxes installed
>configure or remove, or install
Regional and Language Settings
>regional settings can be changed, such as
*format of numbers (e.g. decimal separator)
*default currency sign
*Time and date notation
*Location of computer
Scanners and Cameras
>shows all scanners and cameras
>configure or remove, or install
Security Center
>only available in Windows XP Service Pack 2
>View and configure-
*Windows firewall
*Automatic updates
*Virus protection
>notifies when such features are enabled, disabled or otherwise compromised
Sound and Audio Devices
*Change sound card settings
*Change system sounds, or program-specific sounds that should be played when a certain event occurs
*Change default devices for various purposes
*Show audio devices, and allow them to be configured
Speech
>settings for text to speech support
System
>basic system settings, like
*Display general information on the comp
*Edit computer name in workgroup
*Manage and configure hardware
*Enable automatic updates
Taskbar and Start Menu
>ehavior and appearance of task bar
User Accounts
>control accounts
>give privileges or revoke them
Computer Management Console
>collection of Windows administrative tools
->manage local and remote computers
->>organized into a single console
3 categories of tools
1. System tools
*Event viewer
>used to manage and view the events in application, security and system logs
*Shared folders tools
>view the connections and resources
*Performance logs and alerts
>collects the data about performance and alerts to the monitor when performance falls below minimum settings
2. Storage
*Removable storage
>information about removable storage media and manages libraries
*Disk management
>manage hard disks and partitions
*Disk defragmenter
>analyze and defragment the partitions
3. Services and Applications
*Services
>manage computer services.
*WMI control
>manage system services
*Indexing service
>manage indexing service and creates index of files
Accessories/System Tools
>provides a quick way to perform many tasks
*Accessibility
>change the size of the screen tool, modify the operation of the keyboard, magnify the part of the screen etc.
*Communications, Entertainment, Games
>Communication provides dial-up networking through which you can connect your computer with a network. Entertainment provides media player, CD player, sound recorder etc for listing music and viewing movies; the games tool provides different games<
*Address book
>store contact information
*Internet tools
>set up your computer to use the Internet
*Accessories
>calculator, imaging, and notepad
>WordPad
>paint
*System tools
>Back up
>Character map
->access to all characters in a font, including those not on the keyboard
>Disk cleanup
->searches the temporary files
>Disk defragmenter
->defragments hard disk
->>rearranging the files so that they occupy continuous blocks
>maintenance wizard, scan disk, scheduled tasks, system information etc.
Command Line
>method of interacting with a computer by giving it lines of textual commands (that is, a sequence of characters) either from keyboard input or from a script<
>simplest form, the user types a command after the computer displays a prompt
>computer then carries out the command
Advantages
*Skilled users are able to use a command line faster than a GUI for many tasks
*Options and operations are often invoke-able in a consistent form
>one "level" away from the basic command
>With GUIs, the available operations and options may appear on different menus with differing usage patterns. may be separated on several different menu levels as well>
*All options and operations are controlled in more or less the same way
*often double as scripting programming languages and can perform operations in a batch processing mode without user interaction
Disadvantages
*CLIs have a steeper learning curve
*CLIs are unsuited to certain tasks, such as image and sound editing
Network Neighborhood / My Network Places
>Windows 95-Network Neighborhood
->folder lists computers, printers and other resources connected to your (LAN)
>Network Neighborhood icon appears on desktop, wether there is a network or not
>also accessible from within Explorer
>designed to replace the drive mapping in older systems, which associates a letter with each shared disk drive
>Many programs still require drive mapping
>required to link two computers Direct Cable Connection
>>Under Windows 9x and Windows NT 4.0 (and above), the Network Neighborhood icon is available on the desktop to assist in the browsing of Windows Network resources. While useful on the local network, this tool is of limited use in browsing the wide area Windows Network, and it is non-functional over PPP. However, equivalent tools exist which work over wide-area protocols such as TCP/IP<<
>My Network Places
->Windows Me, 2000 and XP
>appears on desktop if you are connected to a network
->left click on the Network Neighborhood icon will show menu listing network comps
>network allows sharing resources such as documents or programs
>each terminal icon represents a different computer
>all have own unique name
>shared drive can be seen all comps on network drive and have programs run on it from different comps
Task Bar / Systray
Taskbar
>found on the lower most side of the screen
>contains the start button, program manager, system tray and other information
>can be configured on some Windows to have a quick launch bar, address bar etc.
>Start menu button and a button for each open application.
>the default location bottom of the screen, and from left to right it contains by default the start menu, quick launch bar, taskbar buttons and notification area or system tray
Taskbar Grouping
>creates more available space on the taskbar
Systray
>area on right side of the taskbar
>displays status of various functions
->>speaker volume and modem transmission
->>Applications also insert icons on the system tray
>disable an application icon in the system tray by right clicking it and selecting a Disable or Exit option, only eliminating it for this session<
Start Menu
>contains commands that can access programs, documents, and settings
Quick Launch bar, introduced with Internet Explorer 4,
>contains shortcuts to applications.
>Windows provides default entries
>absent by default in Windows XP, can be enabled
>last part of the taskbar is called the notification area
>contains mainly status notifications
>clock by default appears here
>applications can put icons in the notification area to indicate the status of an operation or to notify the user about an event<
>Other toolbars may be added to the taskbar, and it can also be placed on top or at the window sides
>Start menu is a launching pad for applications
>used to turn the machine off
>contains shortcuts to the programs
>installation programs place an icon in the Start Menu's programs
>can also drag icons of applications from the desktop or from any Explorer window onto the Start menu
>can rearrange their position by dragging them up and down the menu
>folder located on the hard drive
>>Windows 95 to Me, it is located, by default, in C:\Windows\Start Menu, and individual users' menus are located in C:\Windows\Profiles\username\Start Menu<<
>In XP, the menu is located in C:\Documents and Settings\username\Start Menu
>all subfolders of the Start Menu folder appear as groups on the menu
Device Manager
>display and control the hardware
>When any hardware device in the computer is not working, it is highlighted in the device manager and the user can identify and fix it<
>lists of hardware, which can be sorted
Windows 95, 98, and ME
-Start >> Settings >> Control Panel >> System icon >> clicking the Device Manager tab
Windows 2000 and XP
-Start >> Settings >> Control Panel >> System icon >> Hardware tab >> clicking the Device Manager Button.
Device Manager Errors
Within device manager the user can identify three types of problems
*Exclamation Mark
>device is conflicting with another hardware device<
*Red X
>device has been disabled, removed or that Windows is unable to locate the device
*Other Devices
>Windows was unable to locate the drivers for the device and cannot determine the type of device being installed
Managing Devices with Device Manager
>provides a graphical view of hardware
>device drivers and resources associated with that hardware
>Using Device Manager to manage devices and their drivers require the following permissions, all of which are granted to Administrators<
*Load\Unload Drivers privilege
*permissions needed to copy files to the system32\drivers directory
*permissions needed to write settings to the registry
Types of functionality
*Determine if the hardware is working properly
*Change hardware configuration settings.
*Identify device drivers that are loaded for each device and obtain information about each device driver
*Change advanced settings and properties for devices.
*Install updated device drivers
*Disable, enable, and uninstall devices
*Reinstall previous version of a driver
*Identify device conflicts and manually configure resource settings
*Print a summary of the devices
Posted by cherrycat, Jun 11 2007, 03:44 PM
NETWORKING CONCEPTS
Cable
-medium through which data is transmitted from one network device to another
-several types of cables
>commonly used with LANs
>>growth of Local Area Networks and client server computing has produced great increase in the amount of cabling used<<
-network can use variety of cable types
>type of cable chosen for a network is related to the network's topology, protocol, and size
>common transmission losses such as attenuation have to be taken care of while choosing type of cable<
-group of insulated conductors enclosed within an insulator
-main function is transmitting signal from one point to another
-can be broadly categorized into 5 types depending on their attenuation, cost, immunity to EMI, skilled labor required for installation etc-
Coaxial Cable
-commonly used in the cable television industry
-can be used in Ethernet networks
-highly resistant to signal interference
-can support greater distance between network devices than twisted pair cable
-consists of a single core copper wire surrounded by an insulator and enclosed in a copper mesh covered inside an outside insulation.-
Types
RG (Radio Guide) 6
-high quality and low transmission loss
-used in areas where over-the-air signals may cause interference for Digital Cable and Satellite TV applications
RG8
-used in "10base5" "Ethernet" networks
-great flexibility with low transmission losses
RG58
-RG58/U Coaxial Patch Cables used for ThinNet
RG59
-RG59/U BNC Patch cables used for video applications such as CCTV, home theatre, etc.
Co-axial cable-
-when compared to twist pair cable can support greater cable lengths between network devices
-highly resistant to signal interference
-costs less that other cables
Plenum
-uses fire resistant material such as Teflon for insulation
-minimizes the amount of smoke in case of fire
-more expensive and less flexible than PVC cable
-used in space reserved for air circulation in air conditioning and heating systems
PVC (Polyvinyl Chloride)
-form of plastic
-widely used in cable insulation
Advantages
-flexible, and economical
Disadvantage(downright dangerous)
-when it burns, it produces poisonous Halogen gases
>fluorine
>chlorine
>bromine
>iodine
Twisted Pairs
-twisting of two insulated wires around each other
-reduce Crosstalk between them
-may be surrounded either by a shield, or similar pairs of wires
-each pair is uniquely color coded when packaged in multiple pairs
-different uses such as Analog, Digital, and Ethernet require different pair multiples
-commonly used to connect telephones and in computer network technology
-classified according to their maximum transmission frequencies
-basically only two types used
>Cat3 and Cat5
Features
*flexible and easy to terminate.
*Cat 5e/6/7 UTP maximum segment length is 100 meters
10BaseT
-specifications for unshielded twisted pair cable (Category 3, 4, or 5) carrying Ethernet signals-
-category 6 relatively new
>used for gigabit connections
Available in two variants
-Shielded Twisted Pair (STP)
>each of the two copper wires are twisted together
>>coated with dielectric insulator which functions as ground for the wires
-extra shielding protects transmission line from leaking of electromagnetic interference from and into cable-
-often used in Ethernet networks
>especially fast data rate Ethernets with Speeds of 10 to 1000 Mbps
Features
*prevents interference efficiently than UTP
*more expensive and difficult to install
*attenuation of UTP cable is much higher than co-axial or shielded twisted pair cable
Drawbacks
*if metallic shielding is not grounded properly at both ends, shield behaves as an antenna and picks up unwanted signals*
*STP is rare because of cost and difficulty with termination
Unshielded Twisted pair (UTP)
-Cat 3, Cat 5/e, Cat 6
10BaseT specification
-most used type of twisted pair cable in Category 5 cabling
-each individual wire is not insulated
-each wire is twisted around each other
-more susceptible to electrical noise and interference
-signal needs to be boosted at shorter distances
-maximum cable length is 100 meters or 328 feet
Types of UTP cabling
*Category 3/Voice
-used in 10BaseT networks
-can transmit data at speeds up to 10 Mbps
*Category 5e/Data
-speeds up to 1000 Mbps (1 Gbps)
*Category 6/Data
-currentfastest standard
-used in Ethernet networks
Fiber-Optic (Single, Multi-mode)
-uses optical fibers to carry digital data signals in the form of modulated pulses of light
-core of fiber-optic cable is made of glass or plastic and the cladding that are enclosed by a protective coating-
-outer insulating jacket made of Teflon or PVC
-kevlar fibers used to strengthen and prevent breakage
Advantages
*Speed
-operates at high speeds in the gigabits range
*Bandwidth
-High-capacity data transmission
*Distance
-due to lack of attenuation signals can be transmitted over long distances without using repeaters
*Resistance
-greater resistance to outside interferences such as radios, motors and electromagnetic noise
Disadvantage
*Expensive and very fragile
Single-mode Fiber (SMF)
-single strand of glass fiber with core diameter less than 10 microns
>one mode of transmission
carries higher bandwidth of data
-approximately 50 times more than MMF
-speeds up to 25,000 Gbps on paper
SMF is more expensive than MMF
-requires a light source with a narrow spectral width
normally used for local area networks
Multi-mode Fiber Optic Cables
-MMF
made of glass fibers with core diameter in the range of 50 to 100 microns
-can carry data of more than 5 Gbps
meets the bandwidth needs high performance applications
-Streaming Audio/video
-Multimedia
-Networking
Next generation of fiber optic patch cable
-10 Gigabit (10GigE)
-has a 50um fiber core
-provides nearly 3 times more bandwidth than the conventional 62.5um fiber optic
- typically used in installations up to 2000 meters in length
-normally used for wide area networks
RS (Recommended Standard) - 232
-standard for serial binary data interconnection
-commonly used in computer serial ports
relatively poor control of signal rise and fall times
-leads to crosstalk problems
good for short connections below 15 meters
because of unbalance circuits, usually not made with twisted pair
usage of unbalanced circuits is responsible for RS-232 being susceptible to problems due to ground potential shifts among two devices<
CONNECTORS
BNC
-British Naval Connector
-standardized connector used with Thinnet and coaxial
*used to connect a computer to a coaxial cable in a 10BASE-T Ethernet network
10BASE-2
-10 MHz baseband cable network extending up to 180 meters
-the 2 is the rounding up to 200 meters without using a repeater
*thin 50-ohm, base-band coaxial cable.
BNC connector is simpler to use and less expensive than other types of coaxial connectors
BNC cable connector
>either soldered or crimped to the end of a cable
BNC T connector
>joins the network interface card in the computer to the network cable
-BNC barrel connector
>used to join two lengths of thinnet cable
-BNC terminator
>closes each end of the bus cable to absorb unwanted signals
-without BNC terminators, a bus network will not function
RJ (Registered Jack)-45
-Cat 5e jacks
-Cat 5e plugs
>standard connector used for UTP cable
most commonly used for
-10Base-T (10 megabit baseband over twisted-pair copper wire)
-100Base-TX Ethernet connectionsa
>also used in network cabling and in telecommunication applications
RJ-45 jacks and plugs have 8 pins
-8P8C connectors
-stands for 8 Position that describes the width 8 Conductor
AUI (Attachment Unit Interface)
*15-pin connector
-used to attach
>coaxial
>fiber optic, or
>twisted pair cables that are found on Ethernet cards
*is physical interface between a network card and Ethernet cable
*AUI using a D-shape connector is an interface from a computer to an Ethernet
->AUI Interface that plugs into an AUI cable, which can be up to 50m long is fitted to the computer or the client in a 10Base5 Ethernet installation<-
*in 10Base-5 Ethernet networks, short cable is used to connect the AUI with a transceiver on the main cable
-In 10Base-2 Ethernet, the NIC connects directly to the Ethernet coaxial cable
ST and SC connectors
>most common connector used with fiber optic cable are:
*ST (Straight Tip) connector
-barrel shaped
-similar to a BNC connector
*SC (Subscriber Connector or Standard Connector)
-easier to connect in a confined space and it is squared faced
-Attaching a connector to an optical fiber takes much effort than copper wire connectors
>ends of the fiber usually have to be carefully cemented and then polished in order to let the maximum light pass through<
-SC and ST connectors are field-installable, multimode fiber optic connectors
-ST connector is used only on NICs for fiber optic networks such as 10BaseFL or 100BaseFX
IDC/UDC
-Universal Data Connector
-Insulation Displacement Connector
>refers to the way by which the connection is made with ribbon cable
*UDC connectors are used to terminate 2-pair STP cable
-no jack (female end) or plug (male end) as it is neutral and both are identical
*connector and ribbon cable are placed in position and pressed
-pins on the connector are designed to pierce insulation on cable and make contact with wire conductor
*IDC or UDC
-two rows of 25 pins on 0.1-inch centers
NETWORK ADDRESSING
-to communicate across a network, terminals within the system need to be able to identify each other >identifier generally is in the form of a name or an address
-all types of networks use Internet addresses
Internet address
-referred to as the IP address
>divided into two parts
Network address
-network address part is used for network identification
Host address
-used to identify a node within the network
to form the internet address
-network address is concatenated with a host address
>identifies a node within a network uniquely
Internet Address Formats
-an addressing scheme for identifying computers over the internet
>internet addressing uniquely identifies a computer
-consists of Network address and host address
>five internet address classes
-each accommodates a different number of network and host addresses
1. Class A 001.x.x.x to 126.x.x.x255.0.0.0 used for very large networks
2. Class B 128.1.x.x to 191.254.x.x255.255.0.0 for medium size networks
3. Class C 192.0.1.x to 223.255.254.x255.255.255.0 for small networks
4. Class D 224.x.x.x to 239.255.255.255 used to support multicasting
5. Class E 240.x.x.x to 247.255.255.25 reserved for future use
Here the character 'x' is used to denote the numbers ranging from 0 to 255
Benefits of Network Addressing
-organizes hosts into groups
>improves security by isolating critical nodes
>>reduces network traffic by preventing transmissions between the nodes that does not need to communicate<<
-launching subnetting or supernetting can make network addressing even more useful
BANDWIDTH
-used to refer to data transmission capacity of network
-greater the bandwidth the more the information can be transferred over that network at one time
-the size of each network connection determines how much bandwidth is available
>E.G.
-if you use a DSL connection to connect to the internet, you have 1.5 Mega bits (Mb) of bandwidth >Bandwidth is measured in bits
>>Bits are grouped into bytes that form text, and other data that is transferred between computer and internet<<
-analog devices
>bandwidth is expressed in cycles per second, or
>>Hertz (Hz)
-digital devices
>expressed in bits per second (BPS) or bytes per second
NETWORK PROTOCOLS
-Network Protocol Levels
>protocols are the special set of rules that allow computers with dissimilar operating systems, network topologies, hardware, etc. to communicate with each other<
-operate at many layers of the network
-can be implemented either in hardware or software, or a mixture
-Usually, only the lower layers are implemented in hardware
>higher layers implemented in software
Network protocols
>Network communication is defined by network protoco
-network protocol is a standard procedure and format that two data communication devices must understand and accept to be able to talk to each other-
Internet
-TCP/IP (Transmission Control Protocol/Internet Protocol)
AppleTalk
>used in many Apple Macintosh computers
IPX
>used on networks made by Novell Corporation
NetBEUI
>used in many Microsoft networks
How network protocol works
<>Signals are sent over computer networks in chunks of information called packets
-network packets mainly consists of two components
*Header information
-network addresses
-type of data being sent
-timing information.
*Trailing information
-error-checking information to verify that a packet of information was received correctly
<>TCP/IP model was created by the U.S. Department of Defense (DoD)
-TCP/IP protocol suite forms the foundation of the Internet
>main protocols in this suite are the TCP and IP protocols , along with the UDP protocol.
-IP - Internet Protocol
most basic underlying protocol for Internet communication
provides "Addressing" over the Internet
-same as postman needs house address to deliver mail
Internet needs IP address to deliver packets to computers
TCP - Transmission Control Protocol
-provides connection-oriented reliable transmission of data over a network
-ensures that information that is sent to a destination, reaches the destination
-If some parts of the information are lost along the way due to network congestion or losses, TCP detects missing parts and re-transmits them-
UDP- User Datagram Protocol
-another important protocol in the TCP/IP protocol suite
>offers best effort (unreliable) delivery of data but has less transmission overhead than TCP
PX/SPX
<>IPX (Internetwork Packet Exchange/SPX(Sequenced Packet Exchange) protocols
*developed by Novell
*used with Novell Netware operating systems to route packets in within a network
-IPX is a connectionless datagram-based network protocol
>fastest routable protocol
-SPX is connection oriented
-Novell IPX network addresses are unique
>represented in hexadecimal format that consist of two parts
* Node number.
* Network number
-IPX network number is 32 bits long
* Node number
-node number
>Media Access Control (MAC) address for one of the system's network interface cards is 48 bits long
<>NetWare IPX Packet Header
Protocol Structure - Novell IPX: Internetwork Packet Exchange Packet Header
* Checksum - when this 16-bit field is set to 1s (FFFF) it indicates that the checksum is not used.
* Packet length - specifies the length of a complete IPX datagram, in bytes. Packet fragmentation is not allowed in IPX. Packets can be of any length, up to the media maximum transmission unit (MTU) size.
* Transport control - indicates the number of routers from which the packet has passed. When the value reaches 16, assuming that a routing loop might be occurring the packet will be discarded.
* Packet type- specifies the upper-layer protocol that should receive the packet's information. It has two common values
5- Specifies Sequenced Packet Exchange (SPX).
17- Specifies NetWare Core Protocol (NCP).
Destination network, Destination node, and Destination socket - Specify destination information.
Source network, Source node, and Source socket - Specify source information
NetBEUI
<>NetBIOS Enhanced User Interface
-extended version of NetBIOS that enables the computers to communicate within a LAN
-introduces the frame format that was not specified as part of NetBIOS
-is often called as NetBIOS frame (NBF) protocol
* NetBEUI works at the Transport and Network layers for LAN.
* the fastest protocol of all
* non-routable transport protocol but provides data transportation
* For transmission within a single LAN, NetBEUI is a good choice keeping performance in mind
* Its interface must be adapted to other protocols such as IPX or TCP/IP for Internet routing
-both NetBEUI and TCP/IP are installed in each computer
>the server is set up to use NetBEUI for communication within the LAN
>>TCP/IP for communication beyond the LAN
<>NetBIOS and NetBEUI developed by IBM
-adopted by Microsoft for its Windows NT, XP and 2000, and Windows for Workgroup products -Novell, Hewlett-Packard and DEC too use it in similar products
NETWORK TOPOLOGIES
<>Topology refers to the way in which the computers are connected in a network
<>Each topology is suited for specific tasks and has its own advantages and disadvantages
-choice of topology is dependent upon the number and type of equipment being used and the cost
5 major network topologies
1. Bus
-set up by connecting all of the nodes to a single line, and the nodes connect only to the bus
-bus networks later began to use specialized central node called a hub to make attaching nodes easier
-hub rebroadcasts all transmissions received from any peripheral node to all peripheral nodes on the network
-peripheral nodes may thus communicate with all others by transmitting to, and receiving from, the hub
>Disadvantage
-any break in the cable will cause all nodes on cable to loose connection to network
2. Ring
-easiest way to add more computers into a network is by connecting each computer in series to the next -when message is intended for a computer is passed, each system bounces it along in sequence until it reaches it's destination-
-by connecting the computers at each end, ring topology can be formed
<>Advantage
-number of transmitters and receivers can be cut in half
>message will eventually loop all of the way around
<>Disadvantage
-single workstation going down can break the entire ring
3.Mesh
-at least two nodes have two or more paths between them
-similar in some ways to a grid network
>linear or ring topology is used to connect systems in multiple directions
-in true mesh topology (also known as full mesh) every node has a connection to every other node
-full mesh is expensive to implement
>partial mesh is more common
>main advantage of mesh is that alternate connections or routes exist between nodes if one does go down<
4. Star
-reduces chance of network failure
-connects all of the systems to a central node central node only
>failure of a transmission line linking any peripheral node to the central node will result in the isolation of that peripheral node
-rest of the systems will be unaffected
5.Hybrid
-use a combination of any two or more topologies
>resulting network does not have one of the standard forms
>tree network connected to a tree network is still a tree network, but
>>two star networks connected together exhibit hybrid network topologies
-hybrid topology is always produced when two different basic network topologies are connected
Network Models
*provide a standard framework to use when designing complex communication systems
*outline standard issues associated with network design
-allow the designer to solve each issue separately, modularizing the solution
*is a framework to use, not a concrete method
Three broad categories
1. Peer-to-peer networks
-also known as Workgroup
-all computers in a peer-to-peer network are both client and server
>no dedicated servers
>>all the computers can act as a resource, providing printers, files, disk storage to the others
>>>all the terminals can work independently
-recommended for small to medium local area networks
>networks with 10 or fewer computers
Advantages
*Easy to install and setup costs are relatively low
Disadvantages
*no expandability and no centralized management
*no central repository for files and applications
*does not provide the security of a client/server network
2. Client/server networks
-lets the network to centralize functions and applications in one or more dedicated servers
>the servers are the heart of system and provide applications and services to other computers
-clients have access to the resources available on servers
-a central server also provides security
Advantages
*Centralized
-Resources and data security can be controlled through server
*Interoperability
-all components work together
*Accessibility
-Server can be accessed remotely and across multiple Operating systems-
Disadvantages
*Maintenance
-can support thousands of clients
>requires a staff to ensure efficient operation
*Dependence
-when server goes down, operations across network will be affected
3. Wireless
NETWORK TECHNOLOGIES
Connectivity Technologies
Basic networks
1. LAN
Local Area Networks (LAN)
-network that spans a relatively small area
-confined to a single building or group of buildings
-connected using different cabling standards, hardware, and protocols
<>typical LAN setup
-computer with a dedicated CPU of its own
-computer is designated as the file server
>all related software controlling the network and that can be shared by the computers is stored here
-Workstations
>computers connected to the server
-less powerful compared to the file server
>allowed to have additional software on hard drives
<>many different types of LANs
-Ethernets most common for PCs
<>Apple Macintosh networks are based on Apple's AppleTalk network protocol
-built into Macintosh
-LANs can transmitting data at very fast rates
>much faster than data over telephone line
>>distances are limited
-limit on the number of computers that can be attached to one LAN
2. MAN
Metropolitan Area Networks
-networks that connect LANs together within a city
>connection between LANs is through a local exchange carrier
-protocols different from those used for LANs.
Examples of MAN protocols
RS232, V35.
Asynchronous Transfer Mode (ATM).
ISDN (Integrated Services Digital Network) PRI and BRI.
* XDSL (many different types of Digital Subscriber Lines).
3. WAN
Wide Area Network
-connects larger geographic areas like two states or few different countries
-can be established over any distance via telephone lines or satellite uplinks
<>main difference between a MAN and a WAN
-WAN uses cabling or radio waves over long distance
>otherwise the same equipment and protocols are used
<>main difference between a LAN and WAN
-LAN typically covers a single office, WAN covers a much wider area
-WAN uses multiplexers to connect local and metropolitan networks to global communication networks -to users, a WAN will not appear to be much different than a LAN or a MAN.
-Internet can be considered as the world's largest public WAN.
4. DSL
<>Digital Subscriber Line
-delivers high-speed Internet access across the existing twisted pair telephone lines to transport high-bandwidth data-
-data signals are sent as changes in voltage on the wire
-enables much higher speeds up to 2 Megabits per second
-DSL modem on the phone line splits the single phone line into two frequencies
>one for data and one for voice
>>allows simultaneous voice and high-bandwidth data over a single pair of copper telephone wires
5.ISDN
>Integrated Services Digital Network
-made up of digital telephony and data-transport services that offered by local telephone carriers
-digitization of telephone network that allows voice, data, text, graphics, music, video to be transmitted over any existing telephone wire-
-ISDN Adapter
>device that allows a computer to transmit over ISDN lines
-lines are capable of transferring speeds in the range from 57.6K to 128K
>provide two data channels
-each will have own phone number
>allows simultaneous voice and data as well as higher speed data transfers using both lines for data
<>Two basic types
1.Basic Rate Interface (BRI)
-basic service and is intended to meet the needs of most individual users
2.Primary Rate Interface (PRI)
-for users with greater capacity requirements
-ISDN adapters operate at the Data Link layer of the OSI model
6. Cable
-high frequency carrier signal is modulated by data
-Cable networking involves distributing the data collected at a central location by means of a network of connecting cables-
>optical fibers or coaxial cables and broadband amplifiers including a Cable modem
-Cable modem
>located at the subscriber's end that lets a computer to get connected to the Internet through an existing cable network connection<
-Very fast
>speeds up to 4Mbps are possible
7. Wireless
-method of data transmission, similar to wired technology
-for both these technologies the range of transmission is prime concern
<>three categories of wireless media
*Radio
-frequency ranges from 3Hz to 300GHz
-broken into many bands
>AM (300-3000 Khz)
>FM (30Mhz-300 Mhz)
>microwave bands (3-30GHz)
-Microwave
>can further be classified into Terrestrial and Satellite
-frequency usually falls in the range of 4-6GHz or 21-23GHz
-speed is usually between 1-10Mbps
-to link networks over long distances, microwaves are used
>two microwave towers should have a line of sight between them
-signals are usually encrypted for the sake of privacy
-transmission frequencies of Satellite are generally between 11-14GHz with a transmission speed in 1-10Mbps ranges
*Infrared
-just below visible range of light ranging between 100Ghz and 1000Thz
>laser or light emitting diode (LED) is used
-Light may interfere with the signal
-infrared signals cannot travel through objects
<>wireless networks allow connecting computers without the need of wires or cables
-data may be transmitted over several different types of transmission medium such as microwave, radio, infrared light, or lasers
<>main disadvantages
-data transmission rates are not as high as wired networks
-security is a concern in wireless
8. Satellite
-orbits at an altitude of 22,300 miles above the earth
-stays in a fixed position relative to the rotation of the earth
>Geostationary orbit.
-ground station on the earth will send and receive signals from the satellite
-signals will have delays ranging between 0.5 to 5 seconds due to the distances
-transmission frequency will normally be in the ranges of 10 to 15 Ghz
-transmission speed in the range of 1 to10Mbps
>GEOs can cover as much as a third of the earth's surface
>can be used in locations where physical Internet access is not available and in devices that move frequently
>available in most parts of the globe, including remote areas like forests and to ships at sea
Posted by cherrycat, Jun 5 2007, 08:10 AM
PRINTERS
->outputs data seen on screen to paper
->older printers use parallel port
->newer ones use USB
->most crucial printer measurement dots per inch rating
->best chosen by actually seeing the quality of output
->>many types of print technologies
->Daisy wheel
->Dot matrix
->Laser
->Inkjet etc
->>impact and non-impact
Impact
->print images on paper using a series of pins or hammers
->>strike on an inked ribbon to create the image
->Dot Matrix
->Daisy Wheel etc.
Non-impact
->do not have contact with the paper while printing
->>Inkjet
->tiny nozzles spray droplets of ink on the page
->>Laser
->uses heat to attach microscopic particles of dry toner to specific parts of page
->>Bubble Jet, etc
Solid Ink Printer
->contains sticks of wax-like ink that are melted and applied to paper
->>ink hardens in place
->capable of creating brilliant, vibrant prints on a wide range of media<-
->>cardstock
->>envelopes
->>transparencies
->>recycled paper and custom page sizes.
->Print Head
->>solid ink applied through precise stainless steel print head with tiny holes smaller than a human hair<<-
->uses 1,236 nozzles jetting more than 30 million drops per second
->print head primarily is used in applying ink to print drum
Print Drum
->ink is jetted from print head to a heated drum where it remains in a malleable state<<-
->>ensures precise transfer to the paper
->>reduces the amount of ink that can wick into the paper fibers and controls dot spread
Phaser Controller
->based on a 500 MHz processor and high-speed 64 bit bus
->brain of the printer that converts data from the computer to information needed to print image<-
cabinet and a tray complete the assembly
->fast
->lower cost per page
->color sticks are easier to load
->>unique shape-coded and numbered ink sticks
->ensure the right color goes in right place
Dot Matrix Printer
->oldest printing technology
-still used because of low cost per page
>Print Head contain a row of “pins” that are triggered in patterns to form letters and numbers as Print Head moves to and fro on paper<
Printing Procedure
>pins are coiled by wire
->held in the rest position by small magnet and spring
>Printer Controller activates a pin by sending signal to Print Head
->Print Head stimulates wires around appropriate print wire turning print wire into an electromagnet
->>electromagnet fires the print pin, thrusting it into the ink ribbon leaving a dot on paper
->>>arrangement of dots in various shapes form characters
Speed
>measured in characters per second
>>CPS no change)
can be differentiated on the basis of speed
>usually varies between fifty to five hundred CPS
Quality
>depends on the spacing of the pins in Print Head
>>early dot-matrix printers used only 9 pins
>>>one single picture and not multiple pictures
>>>>resulted in an output that looked “fuzzy” or have “draft qualiy
>>>dots were spaced at a distance from each other
more pins had to be put closer together on print head for better quality<
>are noisy when compared to others
>have the ability to print carbon copies of original document
Ink Dispersion
>Inks are a complex mixture of pigments, varnishes, waxes, solvents and other additives<
>manufacturers blend carefully and milled crushed ingredients,ensuring smooth, homogenous product free of lumps or large particles<
>disperses ink through tiny nozzles
>>the primary way of printing adopted by majority of non-impact printers<
>Ink Jet
>Bubble Jet
INKJET PRINTER
Print Assembly
{Print head
>contains series of nozzles used to spray dots of ink
Ink Cartridge
>store or a repository for ink}
Stepper Motor
>transports print head assembly from one corner of the page to other<
Belt
>keeps print head assembly and stepper motor securely fastened to one another<
Stabilizer Bar
>makes sure that print process goes through with precision, accuracy and control<
Paper Feed Assembly
>Paper tray/Feeder
>>where paper can be loaded
>Feeder
>>pulls open at an angle and can be located at the back of printer >main advantage that a paper tray has over a Feeder is that feeder cannot hold many pages
Roller
>aids in smooth transfer of pages from paper tray into printer
Paper Feeder
>Stepper Motor
>>supplies power to the roller and ensures that papers are fed at a uniform speed<
>>>enables printer to print seamless image
Transducer
>located at the back of reservoir of each nozzle
>receives a tiny electric charge that causes it to expand
>>expands inward forces a tiny amount of ink out of nozzle
>>recedes out, pulls some more ink into reservoir to replace ink sprayed out<<
BUBBLE JET
{>designed in similar manner to ink jet printer
>>ink cartridge
>divided into several small chambers
>>each chamber has metal plate and tube
>>>Ink is supplied from the top of tube
>at bottom of each chamber is small pinhole which is used to spray ink
>>print head}
>for chamber to spray ink it is stimulated by an electric signal sent to heating element<
>>heat vaporizes ink from element and causes it to expand, pushing ink out of pinhole in form of bubble<
>vapor expands
>>bubble eventually gets large enough to break off into a droplet
>rest of the ink is pulled back into chamber by surface tension of ink
>if another drop needs to be sprayed, entire process is repeated
>>upon completion of job, printhead docks itself in maintenance station
>small suction pump and ink absorbing pad pull the ink through the nozzles using vacuum suction and absorb the expelled ink
>>keeps printer in good condition
LASER PRINTER
>main principle behind working of a laser printer is Static Electricity >>atoms with opposite charges attract each other
>uses this energy as temporary glue
>most important part is the photoreceptor
>>consists of a cylinder or a drum that revolves
>highly photoconductive material that is dispersed by light photons creates drum or cylinder
>>consists of
*Toner
*Corona wire
*Quartz lamp
*Laser unit
*Fuser
*Developer roller
*Photoreceptor drum assembly
>computer sends printed matter to printer as vector information
>>vector information is converted into dots
>Laser Unit
>>located at the back of the printer
>shoots the laser beam while printing
>>laser fires when there is a dot
>remains off when there is blank space
>>vector information is converted into dots
>onboard electronics control movement of laser and beam is passed through lens filter to Photoreceptor drum<
>>corona wire gives complete positive charge is given to drum when it starts rotating<<
>corona wire is a wire that carries electrical current and which runs through it<
>>when drum rotates, miniscule laser beam hits across the surface in order to discharge certain places<<
>laser moves in a horizontal pattern
>>creates dot patterns on photoreceptor drum
>once entire line of dots is complete drum rotates to receive next line<
Process
*laser hits the positively charged drum, negative charge is created
*toner is electrically charged powder
>>two main components
>Pigment is responsible for imparting colour
>Plastic
>>pigment blended with plastic particles to avoid smudging and make image look sharp<
*laser hits the drum
>positively charged toner attaches to negatively charged regions of drum<
*paper is passed over drum
>paper is negatively charged by transfer corona wires
>>charge is greater than negative charge on drum
>>>attracts positively charged toner pigment
*paper is neutralized and passed through fuser assembly
>Fuser Assembly is a Teflon coated metal roller
>>heated by a quartz lamp
*heat fuses pigment to paper
*pattern is cleaned off the drum using the charged corona wire
>printer is ready for the next page.
Clean-Charge-Write-Develop-Transfer-Fuse
California-Cows-Won't-Dance-The-Fandango
Printer Interfaces
>enables printer to communicate with computer
>defines time interval and amount of data to be transferred
>combination of both software and hardware
>some printers can support more than one interface
>several components make up interface
-communication type
-interface software
>each aspect must be matched on both printer and computer
-parallel port then appropriate parallel cable coupled with proper software, based on the platform, must be used
Ports(Hardware)
*Serial
*Parallel
*USB
*Network
Serial
>data is sent serially i.e. one bit after another
>bits form a queue and enter the printer one by one
>also known as Communication (COM) ports
-bi-directional
->allow transfer of data in both directions
>have a maximum transfer rate of around 115 kbps (kilo bits per second)<
-cannot receive or transfer more than 115kbps of data
->newer ports support greater speeds
>either 9 pins or 25 pins
-each pin has a specific purpose
Parallel Ports
>support higher data bandwidths than serial ports
>much faster
>eight bits at a time over eight separate wires (one for each bit).
>male DB-25 connector and a male 36-pin Centronics connector at either ends of a parallel cable enable communication<
-DB-25 connector connects to the computer
-Centronics goes with the printer
->shorter than 10 feet long
USB
>has higher data transfer speeds
>recognizes new devices automatically
>single, standardized, easy-to-use way to connect up to 127 devices to a computer<
>hot-swappable
>many USB devices can be put to sleep when computer enters power-saving mode<
>newer USB devices support data speeds up to 480mbps (megabits per second)<
Network
>printers can be hooked directly onto the network, enabling all the computers on the network to access printer<
>newer printers (primarily laser printers) have this special interface<
-network interface card (NIC) and ROM-based software
>type of network interface used on the printer depends on type of network printer is being attached to<
>E.G.-if you're using a Token Ring network, printer should have Token Ring interface<
Printer Drivers
>software that drives the printer
>when printer first connected to computer, driver has to be installed and configured to interface in order to enable computer to communicate with printer<
>driver is made for specific type, model and operating systems and to enable user to use all the features of printer<
>complex pieces of software
>source of many problems, such as:
*Last character on every line is missing
*Printout is covered with solid black boxes
*Nonsensical characters appear
*Program crashes when printing and operating system reports an error*
*many other problems that can happen due to erroneously configured or outdated driver software*
Cause
>driver poorly written, or older version or inappropriate version for OS or have some bugs<
Solutions
*Get updated printer driver
*Use a different compatible printer driver
*Change format
-drivers behave better on simpler tasks
-do not change drivers frequently
-try changing them if existing driver is not suitable for printing in specific format
Paper Feed and Output
-does not feed paper
-feeds multiple pages
-paper is jammed.
Cause
*paper feed rollers may be worn which causes the rollers to slip on paper
*sensor flag may be in wrong position or not moving freely
*drive gears could be worn or jammed
*something is blocking the paper
Solution
*click the 'Eject' option in printer software or 'Eject' button on printer
Check
*Paper isn't too old or creased
*Paper is loaded as per instructions in manual
*Edge guides are set correctly
*Paper isn't too thin or rough
*Use paper that meets paper requirement for printer as indicated in manual
Calibration
-Calibrating printer insures that what is printed is consistent with what is seen on-screen
-calibration utilities allow users to correct changes in print quality caused by changes in temperature, humidity, toner/ink, paper and use over time-
Errors
Printer error codes
-displayed on the LED display
>number or a term or simple flashing of the LED at different frequencies
-number displayed will point in the right direction
E.G.
*ERROR 11 - Paper out
*ERROR 12 - Open or no cartridge
*ERROR 13 - Paper jam
*ERROR 14 - No ink cartridge or No toner cartridge
*ERROR 16 - Toner low message
*ERROR 24 - Job memory full
Print Quality Problems
*Horizontal banding
*Vertical misalignment
*Colour gaps
*Blurry or smeared printout
Causes
E.G.
*Cartridge low on ink
*Incorrectly configured driver or printer settings
*Dirty or crumpled paper
*Clogged nozzles
*Faulty components
Solutions
*Ensure the paper is not damaged, dirty or too old
*the printable side of the paper is face up in sheet feeder
*run Nozzle Check utility bundled with printer driver
-Inkjet and Bubble Jet printers
*run Head Cleaning utility to clear any clogged ink nozzles
-Inkjet and Bubble Jet printers
*run Maintenance utilities bundled with printer driver software for laser printer<
Connections
>cables should be well shielded in order to avoid magnetic or electrical disturbances<
-cause garbled printouts and damage hardware
>plug connectors in the right ports
>don't force a connector into a port if it doesn't slide in smoothly
>network protocol has to be properly configured to facilitate a smooth and error free flow of data<
Posted by cherrycat, May 14 2007, 11:26 AM
Motherboard, Processor and Memory (THIS should be Fun.)
Motherboard-
Computer's main circuit board
Contains
-connectors
-ports
-controller chips for keyboard, disk drive, etc.
[u -All controller chips together called chipset
[u]Processor-
Also CPU (central processing unit) performs actual data processing
-data obtained via system bus from main memory -results sent back to main memory
-computation, co-ordinates, controls major component operations
-two main components
-Control Unit
-Arithmetic Logical Unit (ALU)
[u]Main Memory-
Stores programs and data either permanently or temporarily
Processor
Larger computers may require more than one
-Control Unit gets instructions from main memory and executes it.
-controls input and output devices, passes data to ALU
-ALU
-performs artihmetic and logical computations
Popular CPU Chips
Many, MANY types
-Pentium most popular
-MHz or megahertz
-clock cycles
-processor needs fixed numbers of clock cycles
-the more clock cycles, the faster it goes
Some Common Chips
Intel Celeron 500-800 Mhz with 128kb Level 2 cache, Full Speed
Intel Pentium II 233-450 Mhz with 512 kb Level 2 cache, Half Speed
Intel Pentium III 450 Mhz-1Ghz with 256 kb Level 2 cache, Full Speed
Intel Pentium III Zeon 600 Mhz-1 Ghz with 256 kb-2 MB, Full Speed
Intel Pentium 4 1.4 GHz - 2 GHz with 256 KB, full speed
Pentium
Pentium
-x86 architecture microprocessor released in 1993.
--486 processor came first
-actually to be named 80586 or i586.
-two versions
--60MHz and 66MHz
Later versions 75, 90, 100, 120, 133, 150, 166, 200 and 233 MHz.
-3.1 million transistors
-32-bit address bus
-64-bit data path
-16K on-chip cache
-60MHz to 200MHz.
--two 486DX chips in one larger chip
---each chip can execute instructions independent of each other
----super scalar
Pentiums need special motherboards
-hotter than previous processors
--need heat sink on top of the processor
Other important changes from 486
--Superscalar architecture
--two data paths=multiple instructions per clock cycle
-64-bit data path
--extracts double the amount of information compared to 32 bit data paths.
- MMX instructions
57 new instructions for better video, audio, and graphics
cache doubled to 32KB
SIMD instruction for multimedia applications
Single Instruction Multiple Data
-one instruction gives instructions to several pieces of data
Pentium Overdrive
upgrade option for older 486 computers
-enhance the 486 performance without paying for full Pentium chip.
just replace the 486 CPU with the Overdrive
-Designed to run two and a half times faster than the motherboard
BUT
Only 32 bit
ran as hot as a regular 64 bit Pentium, requiring extra ventilation
Pentium Pro
-sixth-generation x86 architecture microprocessor
-could meet the needs of a server
rectangular Socket 8
-up to 200MHz
150, 166, 180 or 200 MHz
in 32-bit operating system using dynamic execution
-256KB, 512 KB or 1 MB L2 cache
60 or 66 MHz external bus clock
-often ran slower than Pentium when running on 16-bit code and operating systems and even parts of Win95 were 16 bit
-Multiprocessor support up to 4 processors
-Two low-power states: Auto-HALT and Stop-Grant
-Optimized for 32 applications.
-Integrated non-blocking second level cache that runs at the speed of the processor
-An exclusive internal bus for level 2 cache
-Separate 8 KB code and 8 KB data level 1 cache
Pentium II
Introduced in 1997
Pentium II uses a Single Edge connector (SEC) instead of PGA
233MHz to over 400MHz.
designed for Multimedia applications
-special on-chip multimedia instructions and high-speed cache memory
Celeron a low-end version
->Pentium II with less (or no) level 2 cache
Pentium II designed for PCs
Pentium II Xeon
->high-end version based on same circuitry but for multiprocessor severs and workstations
slot-based form-factor instead of a socket one
->separates the secondary cache from the processor; yet keeps it on a closely coupled bus
->slower (ran at half the processor speed) but was cheaper
Pentium II (Klamath)
Slot 1
original Klamath Pentium II ran at 233 and 266 MHz
inadequate 66 mhz bus
300 MHz released in 1997
Pentium II (Deschutes)
Deschutes core Pentium IIs released in 1998
Slot 1
333 MHz
ran cooler than Klamath
100 MHz FSB speeds
Pentium IIs of 266, 300, 350, 400, and 450 MHz were also released
Pentium III
x86 based architecture microprocessor introduced in 1999
similar to Pentium II
->major difference addition of SSE instructions.
-SSE (Streaming SIMD Extensions) adds better floating point support (128 (4X32) bit registers) for graphics demands
70 new instructions and was optimized for voice recognition and multimedia
PSN (processor serial number) added
->unique number electronically encoded into processor
Pentium M is an improvement on the Pentium III design
Pentium III Cores
Katmai
Sample
labeled as a Pentium II
initial Katmai very similar to the Pentium II
only differences introduction of SSE
->improved L1 cache controller
initially released at 450 and 500 MHz
Later on released at 550 MHz and 600 MHz
Slot 1
Coppermine
Slot 1
was released in 1999
integrated full-speed 256 KB L2 cache
500, 533, 550, 600, 650, 667, 700, and 733 MHz
-750, 800, 850, 866, 900, 933 and 1000 MHz (1GHz) during mid 2000
Coppermine-T
third version
Tualatin (Coppermine-T)
released during 2001
trial for Intel's new 0.13 process
intended for servers where power consumption matters most
good performance especially with variations that had 512 Kb L2 cache (calledPentium III-S)
1.0, 1.13, 1.2, 1.26, 1.33 and 1.4 GHz till early 2002
Slot 1
Pentium 4
Introduced during end 2000
1.4 and 1.5GHz
->NetBurst micro-architecture
First a 400MHz system bus (FSB)
->evolved to 533 and 800MHz
Contained 42 million transistors
initially built with 180 nanometers process technology
moved on to 130 and 90->
first chipset supported Rambus memory only
chipsets that followed used more common DDR SDRAM
Willamette
first Pentium 4
1.3, 1.4 and 1.5GHz
released in competition to AMD Athlon
initially utilized socket 423
later revisions moved to socket 478
inexpensive but handicapped by need for expensive Rambus Dynamic RAM (RDRAM )
Northwood
2.0 and 2.2 GHz released in January 2002
secondary cache size 512k
socket 478 Socket 423??
April 2002
->2.4 GHz P4
->2.53 GHz part in May (the bus speed was increased from 400MHz to 533MHz) ->2.6 and 2.8 GHz in August
->3.06 GHz Pentium 4 in November
P4s in the 2.4 to 2.8 GHz range were fastest chips available
Main difference in new versions was that they supported Hyper -Threading and had system buses at 800 MHz
Pentium 4 Extreme Edition
September 2003
aimed at gamers
same motherboards as P4
->2 MB of Level 3 cache added
socket 478
->800MHz bus
late 2004 new 3.73GHz Extreme Edition
bus speed was increased from 800MHz to 1066MHz
mostly found to be slower than the 3.46GHz
Pentium 4 Prescott
February 1, 2004
core has a 90nm process
major reworking of P4's micro architecture
Northwood runs slightly faster
fastest Prescott-based processor is 3.8 GHz
generated approximately 60% more heat clock-for-clock compared to Northwood With a shift in socket type, from Socket 478 to LGA775 average temperatures were slightly lowered
severe thermal problems caused Intel to abandon the Prescott
plans for 4GHz processors were stalled by Intel in favor of dual core processors
Pentium-D
two connected cores
Power consumption estimated above 130 watts
1066 MHz main difference between the EE edition of P-D and other mainstream models along with retaining the Hyper Threading technology for each core
Pentium M
x86 in March 2003
designed for use in mobile computers such as laptops
code named "Banias"
modified version of the Pentium III design
optimized for power efficiency
runs with very low average power consumption and lower heat output than desktop
runs at a lower clock speed when compared to Pentium 4 but with similar performance
Other power saving methods
->dynamically variable clock frequency and core voltage, letting the Pentium M run slowly (typically 600 MHz) when the system is idle
Banias
first Pentium M
1.3-1.7 GHz
quad-pumped 100 MHz FSB
1 MB L2 cache.
Dothan
May, 2004
improved Pentium M processors (with 140 million transistors)
->Pentium M 715 (1.5 GHz), 725 (1.6 GHz), 735 (1.7 GHz), 745 (1.8 GHz), 755 (2.0 GHz), and 765 (2.1 GHz)
Yonah
mid September 2004
dual-core design
Intel's first dual-core processor designed from scratch
contains two cores based on Banias/Dothan
2MB L2 cache shared by both cores
arbiter bus controls L2 cache and FSB access
single core version Celeron M
Voltage
Pentium processors have operating voltage printed on the label at the end of box Proper voltage must be supplied to the processor
Voltage could be supplied by a regulator on the motherboard OR
->VRM (Voltage Regulator Module) installed in the Header 8 on motherboard
Speed
Clock Speed(GHz/MHz)
->Speed of the processor's internal clock
dictates how fast the processor can process data
MHz (megahertz, or millions of pulses per second)
GHz (gigahertz, or billions of pulses per second)
Front Side Bus(GHz/MHz)
->connecting path between the processor and other components such as memory controller hub
FSB speed measured in GHz or MHz
Cache(MB/KB)
->temporary storage area for frequently accessed or recently accessed data
data stored in a cache speeds up the computer
Cache size measured in megabytes (MB) or kilobytes (KB)
Cache Levels
Cache memory fast storage area used to store frequently used data and instructions
uses a small amount of physical RAM for storage
L1 cache
Level 1 cache also known as L1 cache
memory cache built into the CPU chip or packaged within the same module sometimes known as primary cache
memory closest to the CPU
L2 cache
L2 cache also known as secondary cache
external to the CPU chip
typically located on the motherboard
L2 cache feeds the L1 cache
L3 cache
If the L2 cache is also integrated on the CPU chip external motherboard cache becomes the L3 cache
L3 cache feeds the L2 cache ->feeds the L1 cache ->feeds the CPU
Sockets / Slots
CPU socket or slot is where the processor is installed
connects a computer's motherboard and the processor
most CPU sockets and processors today pin grid array (PGA)
->the pins on the underside of the processor are inserted into the socket
usually with Zero Insertion Force (ZIF)
Slot based processors are cartridge shaped and fix into a slot that looks similar to expansion slots
Slots
Slot 1 - Celeron, Pentium II, Pentium III
Slot 2 - Pentium II Xeon, Pentium III Xeon
Slot A - Early Athlons
Slot B - DEC Alpha
Sockets
Socket 1 - 486
Socket 2 - 486
Socket 3 - 486
Socket 4 - Early Pentiums (60-66)
Socket 5 - Pentium, IDT Winchip C6, Winchip 2
Socket 463 - (also known as Socket NexGen) - NexGen Nx586
Socket 6 - Intel 80486
Socket 7 - Pentium
Super Socket 7 - Faster Bus Speed - AMD K6-2, K6-III, Rise mP6
Socket 8 - Pentium Pro
Socket 370 - Celeron, Pentium III, Cyrix III
Socket 423 - Pentium 4 but short lived
Socket 478 - Intel Celeron, Pentium 4
Socket 479 - Mobile Pentium
Socket 775 - (also known as LGA 775 or Socket T) - Intel Pentium 4
VRM's
Voltage Regulator Module
used for supplying proper voltage to the processor
VRM installed in Header 8 on the motherboard
Most VRMs have VID (Voltage ID)
allows the processor to program the correct voltage during power-on
f motherboard has Header 8, then a VRM must be installed in the header to power the processor
High-performance computers use multiple microprocessors
use one VRM for each microprocessor
multiple VRMS are designed to share the total current demand of the processors
Memory
RAM - Random Access Memory
->Random means contents of each byte of storage in the chip can be accessed directly without accessing the bytes before or after<-
require power to retain their data
data must be saved to disk before power-off
All data processing and program execution takes place in memory
data is copied into memory from storage devices or from network
->moved from memory into the processor for analysis and execution
->instructions from input device direct computer to input data into memory
->once the data is in memory, it is processed and copied
->results are sent to an output device
ROM
retain data and programs forever, even without power
Masked ROMs
very first ROMs
hardwired devices
->contents had to be specified before chip production
PROM
programmable ROM
once programmed PROM's contents can never be changed
EPROM
erasable-and-programmable ROM is programmed in the same manner as a PROM
can be erased and reprogrammed repeatedly
erased by exposing it to a strong source of ultraviolet light which resets EPROM
Hybrid memory
->can be read and written as desired like RAM, but maintain their contents without electrical power, like ROM<-
EEPROM
Electrically-erasable-and-programmable
erase operation is accomplished electrically
Flash memory devices
->high density, low cost, nonvolatile, fast and electrically reprogrammable
technologies for flash and EEPROM are similar
flash devices can only erase sector by sector but not byte by byte
sector sizes are in the range 256 bytes to 16KB
despite this disadvantage, flash is much more popular than EEPROM due to its advantages.
NVRAM
Non-volatile RAM
similar characteristics as other hybrid
is physically different
usually just an SRAM with a battery backup
power turned on, NVRAM operates like any other SRAM
power turned off, NVRAM draws just enough power from the battery to retain data
RAM Types
Many types of RAM
Static RAM
SRAM
retains its contents as long as there is power
if the power is lost even temporarily, its contents will be lost forever
faster than DRAM more expensive
used only where access speed is extremely important
Dynamic RAM
DRAM
extremely short data lifetime about four milliseconds
effective whenever large amounts of RAM are needed
Besides SRAM and DRAM, there are EDO RAM, VRAM (graphics), SDRAM (next level of DRAM), DDR RAM (Next level of SDRAM) and RDRAM
EDO
Extended Data Out RAM
-increases performance by eliminating memory wait states, eliminating a few steps to access memory-
read time does not expire until an additional signal is sent to the chip
-DRAM discharges its contents after read and must be refreshed before another read can occur-
more expensive than DRAM, less expensive than SDRAM
-72-pin SIMMs and sometimes even on 168-pin DIMMs (dual inline memory modules)
DRAM
Dynamic random access memory
enhancement over SRAM
different approach towards storing the 1s and 0s
stores information as charges in very small capacitors, instead of transistors
stores each bit of data in a separate capacitor
if charge exists in a capacitor, is 1
absence of a charge is 0
uses capacitors instead of switches
capacitor leaks electrons, information gets lost eventually, unless refreshed periodically-
uses a constant refresh signal to keep the information in memory
it must be refreshed periodically, so is called dynamic memory
Needs more power than SRAM to refresh signals, mostly found in desktops
uses several memory units called cells
cells are packed with very high density
hold large amounts of data.
also known as FPM (fast page mode) DRAM
comes in 80, 70 or 60 nanosecond (ns) speeds
takes two processor wait-states each time a read or write takes place
compatible with just about everything
Disadvantage-slowest of the memory types-it isn't in demand-more expensive than faster memory such as EDO and SDRAM-
30- or 72-pin SIMMs
also available in DIMMs
SRAM
Static Random Access Memory
type of semiconductor memory
static means that the memory retains its contents as long as power is on
only time the data on the memory is refreshed or changed is when an actual write command is executed-
very fast, but more expensive than DRAM
often used as cache memory due to its speed
random access means that locations in memory can be written or read in any order regardless of the memory location that was accessed before-
symmetric circuit structure allows the value of a memory location to be read much faster than in a DRAM-
Fast SRAM faster than DRAM
-used where speed is most important
slow, low-capacity SRAMs are used where low power consumption and low cost are most important-
power consumption of SRAM varies depending on speed
fast SRAM requires more power than DRAM
Slow SRAM like battery-powered "CMOS" RAM has very low power consumption-
Types of SRAM
Async SRAM
older type used in many PC's for L2 cache
works independently of the system clock
Sync SRAM
synchronous
-synchronized with the system clock.
Pipeline Burst SRAM
most commonly used
requests are pipelined
-larger packets of data re sent to the memory at once
acted on very quickly
can operate at bus speeds higher than 66MHz, so is often used
VRAM
Video RAM
RAM dedicated for displaying bitmap graphics in graphics hardware
resides on the motherboard physically and is separate from the main RAM
a few systems share VRAM with system RAM
the term VRAM used more specifically in high performance graphics hardware used to constantly refresh the display
responsive to modifications from system
Dual Ported VRAM allows graphics processor to read from memory and redraw the screen simultaneously-
SDRAM
Synchronous DRAM
introduced in 1996
developed to match the ever-increasing processing speeds of Pentium
synchronized to the speed of the systems (e.g. PC66 SDRAM runs at 66MHz, PCIOO runs at 100M HZ, PC133 runs at 133MHz and so on)
Synchronizing the speed of the systems keeps the address bus from having to wait for memory because of different clock speeds-
timing is synchronized to the system clock
running in sync to an external clock signal it can run at the same speed as CPU/memory bus eliminating the CPU wait states-
chip is divided into two cell blocks
->data is split between the two
->as bit in one block is accessed, bit in the other is buffered for access
allows SDRAM to burst subsequent, contiguous characters at a much faster rate than the first character
SDRAM are DIMMs
->168-pins running at 3.3 volts
DDR SDRAM
double-data-rate synchronous dynamic random access memory
designed to double the clock speed of the memory
transfers data on both rising and falling edges of the clock signal
->100 MHz DDR system has an effective clock rate of 200MHz
data transferred 8 bytes at a time gives a transfer rate of 16 bytes
with a bus frequency of 100 MHz gives a max transfer rate of 1600 MB/s
184 pins
->can be differentiated from SDRAM DIMMs by number of notches
->>DDR SDRAM has 1, SDRAM has 2
DDR operates at a voltage of 2.5V->3.3V for SDRAM.
->reduces power usage
some new chipsets use DDR memory in dual or quad channel configurations
->doubles or quadruples effective bandwidth
recommended to use a matched pair of memory modules
->pair must have the same size, speed, and latency timings
DDR2 SDRAM
Double Data Rate Two Synchronous Dynamic Random Access Memory becoming the mainstream standard for PC memory
part of the SDRAM family of random access memory technologies
advantage DDR2 has over DDR is ability to work at higher effective clock speeds
XDR DRAM
high performance RAM
3.2 GHz, providing up to 6.4 GB/s bandwidth
the official choice by Sony for the Play station 3 console.
RDRAM
Rambus Dynamic Random Access Memory
can transfer data up to 1.6 billion bytes per second
consists of the RAM, the RAM controller, and the bus connecting RAM to the microprocessor and devices in the computer that use it-
184 pins
available in RIMM
recognized by their aluminum sheath called a heat spreader
Form Factors
describes the size, configuration, or physical arrangement of computer hardware
size and the arrangement of a computer case or its internal components such as a daughterboard<-
SIMM
Single In-line Memory Module
small circuit board with integrated circuit chips used to hold RAM
SIMMS clip into the memory expansion socket s on motherboard
minimal consumption of board surface
easy to install
metal leads on either side of the board electrically tied together
older type of memory module
difference from a DIMM being that the contacts on a SIMM are redundant on both sides of the module<-
30 Pin SIMM
first variant
30 pins
transfers 8 bits of data (9 bits in parity versions).
72 Pin SIMM
second variant
also called PS/2 after the IBM line of computers in which first used
72 pins
transfers 32 bits of data (36 bits in parity versions)
differentiate these two by the number of pins or connectors
72-pin 3/4 of an inch longer than 30-pin
->has a notch in the lower middle
to install , the module should be placed in the socket at an angle
rotate into position
remove the module,
->two metal clips at each end part to the side
chip must be tilted back and pulled out
DIMM
Dual In-line Memory Moduleis
assembly of several memory chips on a single PCB
have gradually replaced SIMMs
SIMMs only had contacts on one side of the card
DIMMs have contacts on both sides that hold twice as many chips
DRAM and SDRAM two types used
EDO DRAM most common type of asynchronous DRAM used
At times also called hyper page mode DRAM
gradually began replacing SIMMs as the predominant type of memory module when Intel's Pentium processors were in the mainstream market<-
most common types of DIMMs
72-pin-DIMMs, used for SO DIMM
144-pin-DIMMs, used for SO DIMM
168-pin-DIMMs, used for SDRAM
184-pin-DIMMs, used for DDR SDRAM
240-pin-DIMMs, used for DDR2 SDRAM
generally either 72 or 168 pins
some 32-bit
more and more are 64-bit
->only have to be installed one at a time in Pentium
DIMMs closely resemble SIMMs
->install vertically into expansion sockets
difference
->SIMM has pins on opposite sides of the board that are tied together
DIMM has opposing pins remaining electrically isolated to form two separate contacts<-
168-pin transfer's 64 bits of data at a time
used in computer that supports a 64-bit or wider memory bus
Major physical differences between 168 and 72-pin
the length of module
the number of notches on the module,
way the module installs in the socket
many 72 pin SIMMs install at a slight angle
168-pin DIMMs install straight into socket
remain completely vertical in relation tomotherboard
SODIMM
Small Outline Dual In-line Memory Module
smaller alternative to a DIMM
about half the size of regular DIMMs
designed for limited space and require low power consumption
often utilized in laptop computers
small footprint PCs (PC's with a Mini ITX motherboard)
high-end upgradeable office printers
72 pins (supporting 32-bit data transfer)
144 pins or 200 pins (both supporting 64-bit data transfer)
144-pin SO-DIMMs commonly found in notebook computers
smaller and thinner than regular DIMMs
MicroDIMM
Micro Dual In-Line Memory Module
smaller than SODIMM
primarily used in note book (laptop) computers or networking
available in 144-pin SDRAM and 172-pin DDR
Each 172 Pin Micro DIMM provides a 64-bit data path
RIMM
Rambus technology
Rambus In-Line Memory Module
At times s wrongly used as an acronym for Rambus Inline Memory Module Officially, "RIMM" is a term trademarked by Rambus Inc
memory module takes up less space inside the computer
has different PIN architecture
similar to DIMMs using Direct Rambus DRAM memory subsystems
RIMM has a 184-pin connector
SO-RIMM module has a 160-pin connector
SO-RIMM is smaller and is used in systems that require smaller form factors
consists of RDRAM chips that are attached using a thin layer of solder
Solder balls on each chip create a metal pathway used to conduct electricity
transfer data in 16-bit chunks
faster access and transfer speed generates more heat
aluminum sheath, called a heat spreader, covers the module to protect the chips from overheating<-
RDRAM
Rambus Dynamic Random Access Memory
transfer up to 1.6 billion bytes per second
subsystem consists of
->random access memory
->RAM controller
->bus (path) connecting RAM to the microprocessor and devices in the computer can be identified by its heat spreader
Motherboard Types
main circuit board of a computer
contains connectors for attaching additional components
controls flow of data and electricity for all components in a PC
two main processing chips
->Northbridge
handles all the data flows to and from the main memory
CPU transactions
->Southbridge
handles the data for most of the ports.
Integrated
->most of the components included into the motherboard circuitry
->designed for simplicity
if one component breaks down, all must be replaced
cheaper to produce, more expensive to repair
ATX mother boards are common integrated motherboards
nonintegrated
->a lot of expansion cards
major components are the video card, disk controllers
->easily identified because each expansion slot is usually occupied by one of the components<-
further classified based on their form factors
->mainly AT and ATX.
AT Motherboard
first modern form factor to be widely used
Advanced Technology
released by IBM in 1984
previous PC and XT form factors were uncommon
a few computers still use AT and Baby AT
current standards are favor of ATX.
not a huge technological advancement from older form factors
biggest advancement was tower design
->power switch in the front
power supply provided 192 watts
-three times more than older ones
12 inches (305 mm)
->won't fit in mini-tower or mini desktop
major problem with the width
->it takes up space behind the drive bays
->>makes installation of new drives difficult
power connectors almost identical with 6-pin cords
->two connectors are not physically distinguishable
would damage of the motherboard when connected incorrectly
Baby AT
variant of AT
introduced by IBM in 1985
popular as they were cheaper and smaller
same functionality as AT
width is reduced from 12" to 8.5"
marginally longer.
both were first PC motherboards to have built in sockets (headers) for I/O ports ->serial and parallel port connectors are attached using cables that go between the physical connectors mounted on back of the case and headers (pin connectors)<-
distinguished by their shape
-keyboard connector is soldered
widely used in 386, 486 and early Pentiums
both have the processor socket(s)/slot(s) and memory sockets at front
long expansion cards and drives designed to extend over them
Older processors and memory chips small and put directly onto motherboard
processors became larger
->form factor did not have space to fit the combination of processor, heat sink, and fan<-
->introduction of SIMM/DIMM sockets made the concept of direct memory installation obsolete<-
ATX form factor
designed by Intel in order to overcome the above issues
introduced in 1995
quickly replaced older Baby AT & AT
Advanced Technology EXtended
rotates the orientation of the board 90 degrees
allows for a more efficient design
->disk drive cable connectors nearer to the drive bays
->CPU closer to the power supply and cooling fan
ATX is not an abbreviation and is actually a trademark that belongs to Intel
AT standard had only a keyboard connector
->other common I/O connectors had to be mounted individually
first computer motherboard include I/O support
first to place all the connectors directly (soldered) onto motherboard
allowed these ports to be put in a rectangular area on back of the system
each maker could define arrangement
AT power button directly connected to power supply unit (PSU)
power could be managed with proper BIOS support
ATX used one large 20-pin power connector
installation easier and safer
->newer ATX specification has 24-pin power connector to support the power requirements of PCI Express<-
maximum measures 12" x 9.6" (305mm x 244mm)
Mini-ATX is 11.2" wide x 8.2" deep
MicroATX
->same benefits as ATX
reduces physical size
improves overall system design costs
reducing the number of I/O slots supported
ATX provides improved Design for Upgradeability, Reduces Drive Bay Interference, Reduces Expansion Card Interference & has Better Air Flow
ATX will eventually be replaced by BTX
NLX
new form factor used in low profile motherboard
->unique design
expansion slots are placed sideways on special riser card
->better use of space
proprietary design motherboard
->some manufactures design and manufacture own designs
components are laid out differently than an AT or ATX, but will work as a PC
BTX
Balanced Technology Extended
replacement for ATX form factor
->proposed by Intel to address some of the issues that arose from using newer technologies, which demand more power and produce more heat on motherboards compliant with the ATX specification<-
Communication Ports in Motherboard
connectors used to connect external cables and devices
use headers on the motherboard
=>headers are groups of pins used to connect devices or ports to motherboard cable runs from the port and is plugged into header
Serial Ports
male 9-pin or 25-pin port
used by slower I/O devices
->mouse or modem
serializes data
Parallel Port
26 pins
used for simultaneous transmission
->one byte at a time
->>over multiple wires
one bit per wire
normally connects printers and scanners
PS/2 Mouse Port
few motherboards provide a header for a PS/2 mouse port not already on the board
5 pins
USB
Universal Serial Bus)
proposed to be the new standard for connecting devices such as keyboards, mice and other external devices<-
some motherboards provide a 10 pin header to connect a port
most have built in ports
IR (Infrared) Port
some boards have 4 or 5 pin headers for one
typically used for wireless communication to IR devices
more common on laptops than desktops
Primary and Secondary IDE/ATA Hard disk Interface
most boards have integrated headers for two IDE channels
40 pins
Floppy Disk Interface
most boards provide a 34-pin header for floppy disk cable
SCSI
some motherboards have integrated SCSI ports or headers
becoming increasingly popular
50 or 68 pins depending on type of SCSI
Memory Slots on Motherboard
usually white
around 3 inch long
placed close to each other
number of memory slots varies from motherboard to motherboard
->appearance of the slots is very similar
metal pins in bottom to make contact with soldered tabs on memory module
small metal or plastic tabs on each side of slot to keep the memory module intact in slot<-
most common types of memory slots are SIMM or DIMM
SIMM
older 72-pin SIMM-type memory
needs to be installed in identical pairs, no mix & match
the two slots are called a bank
Banks is a method by which a system addresses memory
must be completely filled with memory modules of the same size and type
3 (3 banks of 1)
3 memory slots
divided into 3 banks
each bank consists of one memory slot
can add memory one piece at a time
4 (2 banks of 2)
4 memory slots
divided into 2 banks
each bank consists of two memory slots
add memory two pieces at a time
must be the same size and type of memory
12 (3 banks of 4)
12 memory slots
3 banks
each bank consists of four memory slots
add memory four pieces at a time
must be the same size and type of memory
DIMM
current standard
168 pin 3 volt un-buffered synchronous DIMM-type memory
found in all newer Pentium II/III, Celeron, Athlon, Duron
can be installed one stick at a time
often matched with different types of DIMMs
Usually all boards allow 384 to 512 MB of system RAM
newer ones beyond 1 GB total system memory
RIMM
16-bit interface
higher speeds than DDR
Intel RDRAM chipsets require RIMMs in pairs over a dual-channel 32-bit interface
Other Components
Processor Sockets
different slots and sockets for CPUs
most sockets are square
precautions are taken to make both socket and processor are in proper orientation. processor usually marked with a dot or a notch in the corner that is intended to go into the marked corner of the socket<-
lots of different sockets and slots
most popular are the Socket 5 and Socket 7, and the Single Edge Contact Card (SECC)
Socket 5 and Socket 7 CPU basically flat
-have several rows of holes arranged in a square
SECC connectors are slot 1 & slot 2
Design Mobo Class Processors supported
Socket 1 |486 | 80486SX, 80486DX, 80486DX2, 80486DX4
Socket 2 |486 | 80486SX, 80486DX, 80486DX2, 80486DX4
Socket 3 |486 | 80486SX, 80486DX, 80486DX2, 80486DX4
Socket 4 |1st Gen | Pentium 60-66, Pentium OverDrive
Pentium|
Socket 5 |Pentium | Pentium 75-133 MHz, Pentium OverDrive
Socket 6 |486 | 486DX4, Pentium OverDrive
Socket 7 |Pentium | 75-200 MHz, OverDrive, Pentium MMX
Socket 8 |Pentium Pro| Pentium Pro OverDrive, Pentium II OverDrive
Intel Slot 1 |Pentium Pro / Pentium II-| Pentium II, Pentium Pro, Celeron.
Intel Slot 2 |Intel Xeon| Pentium II 400,450, Pentium Xeon
Socket 370 |Celeron| Celeron, Pentium IIIs
Socket 423 |Pentium IV| Celeron, Pentium Iv
Socket 479 |Pentium M | Pentium M
Slot A - Original AMD Athlon processors
Socket 462 - Newer AMD Athlon, Athlon XP, Sempron, and Duron processors
Socket 754 - Lower end AMD Athlon 64 and Sempron processors with single-channel memory support
Socket 939 - AMD Athlon 64 and AMD Athlon FX processors with dual-channel memory support
Socket 940 - AMD Opteron and early AMD Athlon FX processors
External Cache Memory
high-speed storage mechanism
Level 2 cache (External cache)
external to the CPU chip
AKA secondary cache
sits between CPU and DRAM
feeds L1 cache
if also integrated on the CPU chip
->external motherboard cache becomes L3 cache
L3 cache feeds the L2 cache, which feeds the L1 cache, which feeds the CPU
on the motherboard in DIP chips or in COAST (Cache On A Stick) slots
speed of L2 cache is directly proportional to the system bus speed
modern computers level 2 cache inside CPU package to shorten bus length and increase the speed to L2 cache
still separate from the CPU core and connected by a bridge
->backside bus
->>runs at half processor speed
level III cache attached to the motherboard runs with bus speed the same as the system bus<-
runs slower than the processor, but faster than main memory
next level of cache is the main memory
->the one after that is called virtual memory
used this when run out of main memory
some use it in other ways
Caution:
For the purposes of the exam, you should remember that the primary (L-1) cache is internal to the processor chip itself, and the secondary (L-2) cache is almost always external.
level of cache is determined referring to its connecting circuits or electronic pathways (bus) and physical proximity to the CPU
Internal Cache (Level I or L1)
small amount of SRAM placed inside CPU and accessed directly
runs at the same speed as processor
486 CPU had 8K of internal cache memory
present computers have 16K - 64K of L1 cache memory
Bus Architecture
bus is a set collection of wires that allows information and signals to travel between components inside or outside of a computer<-
consists of components like the external bus, the control bus, the data bus, address bus<-
external lines are also called system bus or expansion bus
allow the processor to talk to device->
control lines responsible for passing control signals across bus which instruct device to read / write data
address lines provide the memory or I/O device with exact locations of data
data lines provide a channel through which actual data is transmitted
larger the bus width, the more data it can transfer
data in a computer is transferred digitally
single wire carries 5 volts to indicate a 1 data bit or carries zero volts to indicate a 0 data bit<-
ISA Bus
original 8-bit bus used in first-generation IBM PCs accepted only 8-bit expansion boards<-
superseded by the 16-bit AT bus, later known as the ISA bus.
VL-Bus
VESA Local bus
originally used with 486 computers
limited in the number of slots to add on devices
Used for expansion cards such as video cards.
PCI Bus
present standard
transfers data 64-bit at a time with rates up to 66 MHz
fastest of the present PCI is PCI express (clock speeds reaching 133 MHz)
(u}COMBO Bus[/u]
combination of VL-Bus and PCI bus
allows use of both types of add-in cards
AGP Bus
designed for video cards
bus masters, and bus slaves
*Bus masters*
devices capable of initiating any bus cycle (memory read/write, port addressing, etc)
*bus slaves*
devices responding to a bus cycle but not capable of initiating them
Expansion Slots
plastic slots 3" to 11" long
most visible on the motherboard
used to install various devices
video, network, sound, and disk interface cards, etc
three main types
*ISA*
Industry Standard Architecture
mostly used until 1997
brown or black color
->two parts, a shorter part and a longer part
some motherboards until recently had slots for older ISA plug-in-cards
now obsolete
8-bit ISA bus operated at 4.77 MHz
16-bit bus operated at 8 MHz
IBM replaced the ISA bus with proprietary Micro Channel Architecture (MCA)
far more advanced than ISA
computer manufacturers responded with Extended Industry Standard Architecture (EISA) and then VESA Local Bus (VLB)<-
*PCI*
Peripheral Component Interconnect
most computers have (PCI) slot
around 3" long
white or cream color
found in any computer that has a Pentium-class processor or higher
uses either 32 or 64 bits of parallel data
with each clock tick, 32 or 64 bit data is transferred over the bus
transferring 64 bits at a time needs very large parallel bus
->minimum of 64 lines in addition required control and signal lines
released using a differential serial bus instead of a parallel bus
known as PCI Express
requires only a few sets of differential lines
newer motherboards will have a PCI Express bus instead of an AGP slot
PCI are 33.33 MHz clock speed with peak transfer rate of 133 MB ps
PCI-X runs at 133MHz on 64 bit bus
are plug and play
*AGP*
Advanced Graphics Port
high-speed point-to-point channel for attaching a video graphics card
accelerates graphics
earlier PCI or ISA slots were used for accelerated graphics video cards
AGP slots designed to be a direct connection between the video circuitry and the PC's memory<-
usually brown
shorter than the PCI slots and located right next to the PCI slots
AGP runs at twice the speed of a memory bus
AGP 1x
66 MHz reaching up to a maximum data rate of 266 megabytes per second using 32-bit channel
Doubled from the 133MBytes/s transfer rate of PCI bus 33MHz / 32bit.
AGP 2x
66 MHz double pumped to effective 133 MHz reaching maximum data rate of 533 megabytes per second using 32-bit channel
AGP 4x
66 MHz quad pumped to an effective 266 MHz reaching maximum data rate of 1066 megabytes per second using 32-bit channel<-
1.5 V signaling
AGP 8x (Pro)
66 MHz octuple pumped to an effective 533 MHz reaching maximum data rate of 2133 megabytes per second using 32-bit channel<-
0.8 V signaling
come in two versions based on physical interface
3.3V and 1.5V cards
require more power
longer than standard AGP cards
->slot remains the same
used in high end computer designing applications employed in architecture machining, engineering and similar fields<-
64 bit AGP slot is also available, using a 64 bit channel
->used in high end professional graphic cards
AGP is Plug-and-Play
BIOS that will automatically configure the card
Once the card is installed & the system is turned on, BIOS will configure the card driver may need to be installed for the operating system
USB
supports data transfer rates of 12 Mbps (12 million bits per second)
single USB port can be used to connect up to 127 peripheral devices
->mice, modems, and keyboards, etc
supports Plug-and-Play
typically located on the back of the computer
sometimes accessible through front-mounted ports
provides easy way to connect USB-compatible peripherals
USB hub used to connect more than two USB devices
127 devices can be attached to the USB busA
hub provides additional ports
hub plugs into a USB port on the computer
->allows more USB ports for other peripherals
powered USB hubs provide better compatibility with cameras and other USB devices than inexpensive un-powered hubs<-
12Mbps USB 1.1 spec is officially referred to as "full-speed" USB
hot- pluggable
USB 1.0 and USB 2.0
USB 1.0 and 1.1
maximum bandwidth of 12 Mbps
USB 2.0 up to 480 Mbps
USB 2.0 ports backward compatible
->USB 1.1 devices can plug into USB 2.0 ports
Chipset
handle core tasks of computer
deals very closely with the hardware
each chipset is designed to work specifically with certain hardware
chipsets dictate not on the capability of motherboard, but what hardware is compatible with it<-
designed to work with a specific set of processorsm
most only support one generation of processors
->design of the control circuitry must be different for each processor generation due to the different ways they employ cache, access memory, etc
controls the flow of information
controls how some system hardware interacts with the CPU and motherboard
controllers for the memory, cache, hard drive, keyboard, etc
direct traffic along the bus
->allow devices to talk to each other without having to go through CPU
describes the architecture of an integrated circuit
chipset of a modem card different than chipset of a Processor
processors have their own chipsets
->Pentium II and Pentium III have slightly different chipsets
PowerPC processors have other kinds
largest chip (chips) on the motherboard
reduce the temperature
-<chipsets can get pretty hot
not up-gradable.
Older systems had unique controllers to handle each task
->data transfer, IRQ assignments, DMA, etc
eventually integrated many of these separate controllers into a single chip
Compatibility Guidelines
followed when hardware components installed on the motherboard or installing the motherboard itself<-
Chassis, thermal cooling system, heat sink support, power supply selection, Voltage etc dictate compatibility<-
generally, motherboards are cooled with heat sinks
large chips such as the Northbridge and CPU have sockets for case fans
newer motherboards have integrated temperature sensors to detect motherboard and CPU temperatures<-
can be done by the BIOS or Operating system to regulate fan speed
most processors include unattached or attached fan heat sink designed to provide sufficient cooling when used in a suitable chassis<-
fan power cable connects to the motherboard power header
power supplies must comply with motherboard design guidelines
motherboard voltage regulation uses electrolytic capacitors
motherboard fits into the computer chassis with screws or clips
many form factors
necessary for the case, power supply, and motherboard to conform to the same standard<-
recommended to check the form factors of motherboards to choose a chassis that complies with its specification<-
Posted by cherrycat, May 1 2006, 10:21 AM
I/O Ports and Cables
What Could Be Wrong
-Cable faulty
-Device faulty
-Wrong BIOS settings
-Wrong Device Manager settings
-I/O port logic might be faulty
-The computer gods might be crazy
Troubleshooting steps
-check for loose connections, damaged cables
-examine sockets
-check BIOS settings
-run hardware diagnostics
Serial
-check for lastest BIOS code
-remove extensions, port sharing equip between device and system
-very cable specifications, try a known good cable
-connect device to different serial port, see if it works
-check com ports enabled and configured in BIOS
COM1 port should be tested first as this usually does not have a configuration problem or a resource conflict
-use the cables provided with new system or motherboard, not the old ones.
Ports may not work due to resource conflict. trying to simultaneously use the devices that are available on COM1 and COM3, or COM2 and COM4, while the default IRQ settings for COM3 or COM4 are not changed, can cause conflict as the pairs share an IRQ setting by default.
To overcome resource conflicts, it is always best to change the resource settings of the COM3 and COM4 ports from the default standards. check settings for communications software and be sure no specific setting for resources such as IRQs. If it exists then make sure that these are set to the correct values for the setup
Parallel
-Loose connections or cables
-wrong drivers or resource settings
Check printer, print plain text file
test on other computer
-check BIOS settings (usually IRQ 7 for LPT1)
if set to 5, might be sound card conflict
-Check ECP mode, some hardware might not work, might need to disable
mode often uses DMA channel 1, try changing to 3
-if printer needs bidirectional communication, make sure the port is set to that
-if multiple parallel ports, check resources
-use cables that come with new system or motherboard
USB
Device, controller or drivers can be faulty
-Check if the USB function of the device is enabled in the CMOS
-check device manager, if not there, or yellow !, BIOS might be outdated
if present, right click Universal Serial Bus (USB) Controller, Select Properties and check for messages in device status
-check drivers click the Universal Serial Bus Controllers entry, right click the USB Root Hub entry, click Properties, Device Manager
-when USB device doesn't install automatically, possible driver conflict
To remove conflicting drivers
-disconnect devices, boot into safe mode
-choose Win 2k, read any alerts
-Device Manager utility >> Select the desired USB device >> Right-click on the device to select Uninstall
-device might be listed under: Universal Serial Bus Controller, Other Devices, Unknown Devices, or a particular device category like the Modem entry if the device is a USB modem
-Start >> select Shut Down from the menu >> Select Restart from the Shut Down Windows screen, click ok
-Now connect usb device
-if not detected, install manually
InfraRed
6 feet(3meters) between devices
clear line between transmitter and reciever
reciver located within 15 degrees of center line of transmission
-to test move devices close together as possible
Troubleshooting
-verify enabled in Device Manager
right click on infrared icon
-check drivers and port conflicts
-check CMOS settings
IEEE-1394 Adapters and Ports
Plug n Play
-installed adaptor card
devices communicate with controller on card, not comp
Few comps have BIOS support
-Check drivers, check that device is recognized in Device Manager
-check cables and connectors, make sure Firewire cable is being used.
SCSI
Check Power and Cables
Unplug all SCSI and connect problem device to computer
Check Drivers
make sure scsi drive is mounted as drive icon
-SCSI utilities programs are available
in Zip drives, check cartridges
Check for
-termination
-duplicate id numbers
-drive not powered on
-SCSI interface not enabled
-resource conflicts
-incorrect cables
Motherboard
check power and cable connectivity
check power supply fan
disconnect external devices
check jumpers and BIOS settings
make sure voltage tab on power supply set right
if uncertain of changers, set BIOS to factory settings
check connectors
check devices for overheating
look fo physical damage or loose contacts
check if processor is overheating
troubleshoot memory
try known good video card
check with vendor for problems on model of motherboard
try known good motherboard
Isolating Problems
If computer keeps crashing after a recovery, then board is likely bad
reseat RAM, if OS won't load
-test mulitple modules seperately
If compy beeps at startup, reseat PCI cards
-For notebooks reseat the mini-PCI bus and then reseat the RAM.
-notebooks, perform Hard Reset
perform diagnostic test
try MSCONFIG
-close all other applications to avoid conflicts
-remove hardware devices one by one
Try system recovery, back up first
if trouble persists, send in for service
check error msgs in Event Viewer
-Start >> Settings >> Control Panel >> Administrative Tools >> Computer Management (or Event Viewer)
CPU Heat
-check fan, ventilation
run diagnostics
-notebook heat issues
run SPEEDSTEP(intel) lower speed cycle
enable battery optimized performance
CPU must be sealed correctly with thermal barrier
check conflicts, reset BIOS
CMOS/BIOS Settings
beep codes differ between vendors
-if it complains battery is low, change battery and reset BIOS
American Megatrends (AMI) beep codes
1 Short beep: Indicates System RAM refresh failure
2 Short beep: Memory parity error
3 Short beep: Base 64-kbytes memory failure
-memory errors, reseat memory
4 Short beep System timer failure
5 Short beep CPU failure
6 Short beep Keyboard controller Gate A20 failure
-different KB or reseat controller chip
7 Short beep Virtual mode exception error
8 Short beep Display memory read/write error
-reseat video card, try different card
9 Short beep ROM BIOS checksum error
10 Short beep CMOS shutdown register read/write error
11 Short Beep Cache memory error
1l (long) - 3 Short beep Memory test failure (non fatal)
1l Long - 8 Short beep Display test failure (non fatal)
-4, 5, 7, 9, and 10-beep errors, it is likely that you will need to have your motherboard repaired or replaced
POST audible/visual error codes
Anything other than a single beep during bootup indicates an error
-most common are keyboard or CMOS battery low error
100-199 System Board
200-299 Memory Error
300-399 Keyboard
400-499 Video, monochrome
500-599 Video, Color
600-699 Floppy
1700-1799 Hard Disk
Processor, CPU
most common problems in a processor are overheating and mis-configuration
problems often related to CMOS
check if processor is loose in socket
Troubleshooting
check compatiblity
try known good processor
physically check for overheating
check it is well-seated
check jumper and BIOS
check voltage settings in BIOS
-Intel 3.3-3.5 volts
check motherboard vendor to see if BIOS needs upgrades
try setting bios to factory defaults
disable secondary cache in BIOS
lower processor speed, it problem is fixed, then it is a heat probelm
if processor is fine, troubleshoot motherboard
STORAGE DEVICES
FDD
Possible problems
-Media failure
make sure not write protected
try known good disk
-disks fail easily
-Incorrect settings in CMOS
-conflict with other hardware
disconnect new hardware
-Drive incompatiblities
-Dirty read-write heads
-Cabling or connection errors
open computer, check connections, reseat connections
-Floppy controller card
-device driver errors
check for driver issues from MS-DOS
-type format a at prompt
invalid media or Track 0 Bad: Try to format another floppy disk.
Invalid drive specification: Ensure that your floppy drive is setup properly in CMOS
-if it still won't format in Windows, might be a problem with windows and it might need to be reinstalled
-drive failure
if nothing works, try replacing data cable, if that doesn't work, if that doesn't, try replacing motherboard
HARD DRIVES
Possible Problems
-Power connection
check power connection and power supply
-cabling
-addressing conflicts
-hard drive controller or SCSI interface
-device drivers
-BIOS settings
-fragmented or corrupt drives
Symptoms
-lights on, there is disply but no hard drive action, no boot
-boots to A drive, but not hard drive
system files missing or corrupt
-computer doesn't boot when turned on
-17xx error code display
-no hard disk motor sounds
-HDD Controller Failure message appears which indicates failure to verify hard disk setup by system configuration file error. A:, C: or D: Fixed Disk Drive error message appears, indicating a hard disk CMOS setup failure
-Invalid Media Type error means that controller can't find a recognizable track pattern
-No Boot Record Found, a Non-system Disk or Disk Error, or Invalid System Disk
system
boot files can't be found
-video works, disk activity light is on, no bootup occurs
CMOS config is wrong
-Out of Disk Space
not enough space on disk
-Missing Operating System or a Hard Drive Boot Failure
MBR is missing or corrupt
Checking Config
During boot up, watch for the BIOS's HDD type information on the monitor. Note type of HDD that BIOS recognizes as being installed. most common error messages with HDD configuration problems are the Drive Mismatch error and Invalid Media Type
Check Master/Slave configs(IDE)
If more than one drive is on a cable, they should all be the same type (all IDE, all ATA100, etc.)
For SCSI, check ID numbers and termination
make sure SCSI and large SCSI support is enabled
Basic Checks
Check extent of hard disk problem. Put a clean boot disk or an emergency start disk in the floppy drive and boot. Execute CD C:\ command to access the C drive, then DIR command. If you see the contents of the drive, the boot files are lost or corrupted, but the architecture of the disk is in place.
Try with the DIR command- /AH or /AS switch (eg: DIR C: /AH or DIR C: /AS) to look for the system files and also the COMMAND.COM file in the root directory.Probably Disk Boot Failure message onscreen.
If hard disk can be accessed with the DIR command, enter the command Copy <filename> C:\ <Filename> (where filename is the name of the file to be copied) at the DOS prompt (with the clean boot disk still in the A drive). The IO.SYS, MSDOS.SYS, and COMMAND.COM system files should be copied from the boot disk (A:) to the hard disk drive (c:). Turn the computer off, remove the boot disk from the A drive, reboot the system from the hard drive.
To check the hard drive on a Windows NT, Windows 2000, or Windows XP use Disk Administrator and Disk Management utilities(partioning and layout)
Start >> Settings >> Control Panel >> Administrative Tools >> double-click Computer Management icon and Select Disk Management
HDD Hardware Checks
If can't access hdd and config settings are correct, troubleshoot hardware
1.Verify the HDD signal cable for proper connection at both ends.
2.Verify the Master/Slave jumper settings to be sure they are correctly set.
3.Check if the system is using the Cable Select option.
4.Check both the ID configuration settings and terminator installations for SCSI drives.
If the problem still exists format the hard disk. If it fails to format the Hard disk or takes too long to format or if any error occurs while formatting, then replace the drive.
CD/CDRW
Configuration Check
Check the Master/Slave jumper settings. Usually, the CD-ROM drive is set up as the master on the secondary IDE channel. If there are three or four IDE devices determine which devices can share the channels effectively.
Operating System Check
CD icon in the My Computer .
-System Properties dialog
-double-click the System icon in Control Panel
-Properties of the CD-ROM drive is found in Settings
Check drivers, if needed, load them or check manufactuers web site.
look for old AUTOEXEC.BAT and CONFIG.SYS files, which may contain commands concerning older CD-ROM, drives and conflict with Windows
Hardware Check
-Is there a CD or DVD in the drive
-Is the label side of the disk facing upward
-Is the disk a CD-ROM or some other type of CD
In case of a stuck disc, insert a straightened paper clip into the tray-release access hole that's located beside the eject button
If the problem persists may have to replace the drive
DVD/DVDRW
Quality of the drive's controller circuitry
quality depends on type of its controller IC
-BIOS extension may not support all of the R/W functions
-All newer drives ATAPI compatible.May not have an effective method of controlling buffer under run errors, which occur when the system transfers data to the drive faster than the drive can buffer and write it on to the disc. The ATAPI compatibility of the chipset ensures that the DVD read functions work well.
-Minimize buffer under runs by placing the DVD writer on an IDE channel.
Also a possibility that the R/W software for the drive is not compatible with the operating system, or with the controller chip on drive. Operating system's multimedia enhancement drivers (DirectX) may not be compatible with the controller or the R/W application.
Always consult the operating system's hardware and software compatibility lists before buying and installing a CD-RW or DVD-RW.
-There are various kinds of writeable DVD drives. Five types of writeable DVD media. Most drives can use only one or two of these types.
*DVD-RAM-rewriteable/erasable media similar to CD-RW, can be single or double-sided. mostly kept in a closed disc caddy.
*DVD-R-writeable/non-erasable media similar to CD-R; some of the DVD-RAM and all the DVD-RW drives can use DVD-R
*DVD-RW-single-sided rewriteable/erasable media similar to CD-RW. DVD-RW drives can also write to DVD-R media.
*DVD+RW-rewriteable/erasable media, similar to CD-RW, but not interchangeable with DVD-RW or DVD-RAM.
*DVD+R-Writeable/non-erasable media, similar to CD-R, but not interchangeable with DVD-R.
-All rewriteable disks must be formatted before use
Most DVD drives come with a region code, all types of DVD may not open or get detected. Region code settings can be changed only 5 times.
Tape Drive
-Media problems
check for worn tapes, or compatability issues
check tape expiration date
-Dirty read/write heads
-Cabling and power connections
-Controller card
-Device drivers
Removable Storage
-check power
-check connectors and cables
-check drivers
-check documentation to see if device needs support application beyond driver
-check any removeable media
-check Device Manager to see that the device has been recognized and to check for conflicting device drivers
-check signal cable, try known good one
Memory
Improper Configuration: Possibly wrong part for your computer or not following configuration rules.
Improper Installation: not seated properly, socket may be bad, socket may need cleaning.
Defective Hardware: memory module is defective.
Common ways compy informs of memory errors
-Computer won't boot, merely beeps.
If computer does not boot, CPU is unable to communicate with hardware.Could be improper installation or failure of the BIOS to recognize the hardware.
Computer boots but doesn't recognize all the installed memory
-Likely wrong kind of memory, such as putting DIMMs in a comp that only uses SIMMs
-Might accept only modules containing memory chips with specific organizations. eg, the VX chipset doesn't work well with 64 Mb chips
-maximum amount of memory the computer can recognize could be lower than the maximum amount that can be physically installed
The computer boots but the screen is blank
-dislodged card
-memory not seated completely
-compy doesn't support the memory
-Crosscheck that you have the right part number for the compy.
The computer reports a memory error
Memory mismatch error
-Use the set-up menu to inform the litle dear that it is alright to have new memory. Follow the prompts. Enter the new amount, select Save, and Exit.
Computer memory or address errors
-Memory parity interrupt at xxxxx
-Memory address error at xxxxx
-Memory failure at xxxxx, read xxxxx, expecting xxxxx
-Memory verification error at xxxxx
Errors often indicate a problem with a memory module, sometimes indicate a defective motherboard or incompatibility between memory modules.
-remove all the memory and check with each module to see whether the problem goes away. If the error is gone then replace the faulty module with a new one
The computer has other problems caused by memory. The Computer Intermittently Reports Errors, Crashes Frequently, or Spontaneously Reboots
-ESD (Electro-static Discharge), overheating, corrosion, or a faulty power supply
-Registry Errors
If registry error prompts repeat, remove the newly installed memory and restart the computer
General-Protection Faults, Page Faults, and Exception Errors
-most common cause is software
Try rebooting
-after installing new memory, remove new memory and see if the errors are gone
The server system manager reports a memory error
If you get this warning then you must replace the system memory
If errors continue after memory replacement, be sure you have the latest BIOS, software service patches, and firmware
Contact the memory vendor for compatibility troubleshooting
Monitor
Monitors should be worked on by authorized technicans.
Many newer monitors have own diagnostics that show if the video fails.
No Picture
check if everything is plugged in and connected
make sure correct connector is selected
Wavy, Bouncing or Oscillating Picture
check signal cable
check adaptor
make sure monitor is tuned to signal(Image Lock)
Ghosting
Check signal cable
adjust Image Effect
check adaptor
Picture too Light or Dark
Check Brightness and Contrast
White doesn't look White
Check color adjustments
Green, red, and/or blue dots remain on the screen
If they are too big or causing problems, contact manufacuterer for replacement
Colors are distorted with dark or shadowed areas
Contact vendor
Screen image is not centered or sized properly
Use Horizontal or vertical in Postitions menu or buttons on front
Picture is fuzzy
check resolution
change size back to normal
Adjust Image Lock or Image Effect
Eliminate accessories
Power indicator is blinking green/amber or amber
Power saving mode, check settings
Cannot adjust monitor with the buttons on the front panel
contact manufacturer
Keyboard
No characters
some keys work, others don't
Keyboard Error - Keyboard Test Failure error
keyboard/Interface Error- Keyboard Test Failure error
six short beeps from POST
Wrong characters
-check your Windows keyboard settings in Device Manager, make sure settings, language correct
301 error code
Unplugged Keyboard error
key is stuck
-use Known Good keyboard
if kb still doesn't work, and config is correct, then the keyboard receiver on board needs troubleshooting. Might need new board
Mouse
Test hardware by using the well known, known good mouse. If that works, the first mouse is likely defective.
-if simple cleaning doesn't fix it, get a new one.
If new mouse doesn't work
-check driver
-check port and CMOS config
if system port is bad, possible to get a USB mouse or other type of port mouse
Mouse Config Checks
Restart in safe mode
If it doesn't work, check hardware and port
If it works, it's a driver issue
-check device manager to check driver
if conflict remove driver and allow plug and play to reinstall
-might need to try to install driver from Windows disk, or vendor
Sound Card
check Device Manager, look for conflicts
select right driver from list, move it to resource window
-Conflicting Device List
remove driver, reboot, allow OS to install proper driver(Plug and Play)
-Look for Multimedia icon in Control Panel, check Device Manager
Sound Card Hardware Checks
Make sure speakers are plugged into proper port(blush..to think I blamed Linux for 2 days..)
Make sure they are on.
make sure microphone is plugged in right port, make sure it is on.
check for enough disk space for file
Make sure stero speakers are connected properly, left and right
Sound card issues are usually resource issues
-check Device Manager for conflicts
one method, remove device, reboot, run Add New Hardware
some cards have own install programs
Video Card
Check Monitor cables and connections
Check card for any visual damage, reseat
Swap card for known good
In case of integrated video, hook up known good monitor
-if it doesn't work...might need new board
check keyboard
check card cable
check power managment, disable it in bios if it seems to be a problem
check driver
-standard PCI/VGA adapter entry in the display settings under control panel means the drivers are not installed for the device
-uninstall bad, install good from vendor
NIC
Make sure lights on backplate are active
-if not, check card in another compy
verify cabling and cable connection
LAN cable tester
Windows reports an error after you double-click Network Neighborhood
check drivers
check Device Properties list for trouble indicators
Test card with any diagnostic ultilites that may have come with the card
The computer hangs when the drivers are installed
change PCI bios settings according to comp and card manuals.
Diagnostics pass, but the connection fails or errors occur
100BT, Category 5 wiring should be used, check network cable
100BT, connect to a 100BT hub/switch
NetWare, be sure that you specify the correct frame type in your NET.CFG file
check duplex mode on adaptor matches setting on switch
The LNK LED doesn't light
check drivers
verify cable connections
try another port on the hub/switch
check duplex mode matches switch
Make sure right kind of cable between adaptor and hub
-10Base-TX, two pairs
-some hubs like crossover, some like straight
The ACT LED doesn't light
check drivers
try accessing a server, network may be idle
try another adaptor
The adapter stopped working without apparent cause
run diagnostics
reseat card, or try different slot
remove and reinstall drivers
The Wake on LAN (WOL) feature is not working
ensure cable is attached and power on
check bios if comp needs to be configured for WOL
Ensure the network cable is fully attached to the adapter
Modems
Internal
-check its hardware and software configuration; then check for system conflicts, and check for correct drivers
External
It's an external peripheral, with the serial port being treated as a separate I/O port
Modem Symptoms
no response from modem
modem won't dial out
doesn't connect after a number has been dialed
doesn't transmit after making connection
doesn't install properly
transmits garbled messages
can't terminate communication session
can't transfer files
COM Port Conflict
IRQ4 line works for COM1 and COM3, and the IRQ3 line works for COM2 and COM4
-first step to take while installing a modem is to check the computer to determine how its interrupts and COM ports are configured
Modem Hardware Checks
Three different kinds of self-diagnostic tests
*The local digital loopback test
*The local analog loopback test
*The remote digital loopback test
Start by running remote digital loop-back test. If successful then problem is remote computer.
-fails then run local digital loop-back test. If positive problem is local computer.
-local digital test fails, run local analog loopback test
-Result is negative, run local loop-back test
-Local analog test fails, problem is located in local modem
Local analog test is successful, problem still exists run the local analog test on remote computer, the outcome of the test will pinpoint the source of the problem.
-To test internal modem, replace with known good
run hardware test
-Monitor external modem through LED lights
Portable Systems
PCMCIA
Check device manager for any icons indicating issues
-turn system off, reinsert card in another slot
Card might be bad, slot might be bad(PC Card controller), OS might not support that card.
-Windows Device Manager displays the PCMCIA socket but no name
problem with the PCMCIA socket installation
remove the PCMCIA socket listing from Device Manager, reboot, see if Plug and play detects and installs
-if it doesn't work, socket not supported by OS
Other PCMCIA cards appear in the Device Manager, card has a question mark, likely the card is damaged.
-try known good card
Batteries
Make sure it doesn't just need recharging
Verify that the power indicator is on
verify that the power cord is securely connected to a live power source
Check all power connectors
troubleshoot the system board
If it runs from power cord, battery needs recharging or replacing
-Some issues
warning about battery not recharging
intermittent system shutdowns when only on battery
system doesn't recognize network connection when on battery
computer and devices are slow on battery
loses time and date when on battery
Docking Stations / Port Replicators
DS offers internal power supply
check to be sure external device is activated, if not working
check speakers are connected to correct jacks
-check docs to make sure sound is not accidentally muted
There are docked and undocked profiles in Windows 2000 and XP
-If a portable is not Plug -n-Play compliant, you must manually configure the profile
Check power cords and connections
Make sure comp is properly inserted
If device connected to docking station doesn't work then bypass docking station/replicator, try to operate peripheral directly with portable. Verify power supply for docking station and peripheral and verify both are on. Reboot portable while attached to docking station. Check signal cables between docking station and peripheral.
Posted by cherrycat, Apr 18 2006, 10:38 AM
Motherboards
Motherboard Chipset- choose a chipset that supports DDR SDRAM or RDRAM
-socket-based processor with a L2 cache and with the highest speed CPU bus
socket type processors should be preferred against slot based processor
-Socket 939 and Socket 754 for the Athlon 64, Socket 478 for the Pentium 4 and Celeron processors
standard or DDR DIMMs that contain SDRAM, DDR SDRAM, or RDRAM
-SIMMS are outdated
One to five or more PCI local bus slots
-ISA outdated
Mini or baby ATX
-supports Pentium 4
AT outdated
- Contain as many built-in standard controllers and interfaces as possible
Level 1 (L1) cache is found in the processor
Level 2 (L2) cache on board
-Running the memory at the same speed as the processor bus reduces the need to have a cache memory on the motherboard
Memory
Processors move fast, Hard Drives move slowly
-RAM is a speedy, umm...interface
MORE=BETTER
-128MB is a minimum amount of memory for running Windows XP
512MB of memory is better
-older computers is 30-pin or 72-pin Single Inline Memory Modules (SIMM)
-Dual Inline Memory Modules (DIMM) modules used today
Check the computer's manual to determine the correct installation sequence for configuration of DIMM
-some can be in any ole slot, some needs to be arranged in sequence based on modules capacity
Hard Drive
Bigger is Nice
-Personal needs
Before replacing, do disk checks and upkeep
-disk scan and defrag
second can simply be added, best to make new one master
BACKUP before anything is done
CPU
When the computer is taking too long to perform a task or to load an application
-consider cache
-check to see if motherboard supports processor
-will you need heat sink, etc.
-RAM and Hard drive unchanged, not enough RAM might bottleneck, reducing your pretty new processors performance
BIOS
Would add support for larger/faster hard drives, plug n play, correct bugs, support faster processers
-In general, if a computer is not able to utilize all the features of new software or hardware, it may need a BIOS upgrade
Adapter Cards
Memory expansion, advanced graphics, sound, I/O expansion, etc.
-ISA (Industry Standard Architecture) Slot,PCI (Peripheral Component Interconnect) Slot, AGP (Accelerated Graphics Port) Slot, PCI-Express Slot
-Video Card
AGP or PCI
-mid-range and faster graphics chipsets no longer support the PCI slot
-AGP has a dedicated direct connection to the processor instead of sharing bandwidth with other PCI slot and motherboard devices.
-AGP can use onboard or motherboard RAM for handling 3D textures
Sound Card
-Older PCI sound cards are very resource hungry and offer a limited sampling rate of 16 bits at 44,100 Hz
Newer PCI sound cards can take the rate up to 24 bits at 96 KHz
-AdLib and Sound Blaster latest standards
Laptop power sources
-Nickel-cadmium.
-Nickel-metal-hydride (NiMH)
rechargable
energy density is higher but at the expense of reduced cycle life
no toxic metals
less prone to memory effect
-Lead-acid.
-Lithium-ion
longer life span than other batteries
do not use poisonous metals
more expensive
-Lithium-ion-polymer.
-Reusable Alkaline.
-Fuel cell
electrochemical device that generates electric power from either hydrogen or from alternative fuels like methanol, propane, butane or natural gas
-environmentally friendly
-Recharging the battery involves replacing the liquid fuel only
-fairly expensive
PCMCIA
Notebook has 2 slots
-Type I, II, and III cards
Hot swappable
-Type I is the original 3.3 mm thick card
memory devices such as Flash, OTP, and RAM, modems and other devices
Type II expands the thickness to 5.0 mm.
-I/O devices such as data / fax modems, LANs, and also mass storage devices
Type III
-10.5 mm and is used for devices whose components are thicker, such as hard drives
Posted by cherrycat, Apr 3 2006, 08:46 AM
Integrated Device Electronics (IDE)
Connects mass storage media
-hard drives
-CD-ROM
-actually called ATA (Advanced Technology Attachment
-controller built in
Most disks today are IDE
EIDE (Enhanced IDE)-2 controllers, 2 channels
ATA-2, Fast ATA or Fast IDE
-supports up to four drives, in master/slave config
-address and IRQ settings backwards compatible
ATA (AT Attachment)&ATAPI (ATA Packet Interface)
Actual name of EIDE interface
-most widely used
-backwards compatible
-ATA/ATA-1 obsolete
ATA-3 / EIDE
-ATA-4 / ATAPI-4 / ATA/ATAPI-4
ATA-5 / ATA/ATAPI-5
ATA-6 / ATA/ATAPI-6-
ATA itself, with one or two drive support is fairly obsolete(?)
ATAPI-offers support for CD-ROMs, CD-R, CD-RW, DVD, Tape disks and some super-floppy disks such as ZIP and LS-120, besides the actual Hard Drives.
Serial Advanced Technology Attachment (SATA)
Serial ATA or S-ATA
-computer bus used to transfer data to and from a hard disk.
-successor of ATA
-Parallel ATA (PATA)
-ATA -thinner, longer cables
Configuring IDE Device
Standard PC comes with 2 controllers
-IDE 0(primary)
-IDE 1
2 devices per controller
-IDE cable with 40 pins has three controllers on it.
-capable of connecting two devices.
-To connect only one device
-plug into the connector (usually black in color), at the end of the cable.
-Two connectors are close to each other
-connector on the far end connects the main-board
Master/Slave/Cable Select
Config Devices On Cable
-Jumpers on Device
-config usually on label on disk
-Master, Slave, Cable Select
-Cable Select provides automatic sensing of position on cable
-Bootable becomes primary Master
-2nd one becomes secondary Master
-CD-ROM secondary slave
For best performance, one drive per channel
-to save IRQ, put 2 devices on one
-disable 2nd controller to free resources
-in BIOS
Remember Master and Slave devices are different for 80-wire cables and 40-wire cables
-Always give 80 wire cable Primary connection
-40-wire cable secondary connections.
-lesser used devices CD ROMs, CDROM Burners and Tape Disks are connected
-master device on end, yet jumpers set slave
80 wire, device on end set as Master
- blue connector attaches to the motherboard.
- black connector attaches to the primary or master drive.
-gray connector attaches to the secondary or slave drive.
PIN 1 marked with stripe (red)
Small Computer Systems Interface(SCSI)
Less common because costs more, and more useful to business, than home
SCSI is bus, rather than interface, like IDE
-bus, rather than controller
-Narrow
-8 bits, 8 devices, 8 SCSI ids ranged 0-7
-Adapter takes 1 id (7)
SCSI-1
-Basic, early, 8 bit
SCSI-2
-Fast Scsi
-16 bit Wide Scsi
SCSI-3
-wider set of different SCSI types
-not a standard, a set of different specs
-Usually start with ultra
SCSI bus contains
-Controller or host adapter
-usually on mother board, or on device
-can be bought as adaptor card
-own BIOS on controller
-SCSI cable
Cable Lengths
-Single-Ended Cable Length Limits
-maximum length of the cable should be 8(6?) meters
-stub length of not more than 0.1 meters
-Differential Cables Length Limits
-maximum cable length can be 25 meter
-stub length of not more than 0.2 meters
-DB-25 (SCSI-1).
-50-pin internal ribbon (SCSI-1, SCSI-2, SCSI-3)
-50-pin Alternative 2 Centronics (SCSI-1)
-50-pin Alternative 1 high density (SCSI-2)
-68-pin B-cable high density (SCSI-2)
-68-pin Alternative 3 (SCSI-3)
-80-pin Alternative 4 (SCSI-2, SCSI-3)
-SCSI device
-linked to controller by cable
-chain like progression
-end MUST be terminated
-passive termination
-bunch of resistors
-clock speed 5mhz
-active termination
-voltage regulator
-led display, common on Fast Scsi, or system with more than 3ft between controller and device
Narrow
8 bit
50 pin cable
-A cable
SCS-1
-Ultra
-faster 20 Mbytes/sec
Fast
SCSI FAST is referred to transfer rates of 10 MB/Sec with a narrow device, and a transfer rate of 20 MB/Sec for a Wide/Fast device
Wide
16 bit
68 pin cables
-P cables
-Ultra Wide
-16 bit
-40 Mbytes/sec
-maximum cable length of 1.5 m (5 ft) with over 4 active IDs
-3 m (10 ft) with 4 or fewer active IDs
Wide Ultra SCSI
-Ultra Wide differential SCSI has a maximum cable length of 25 m (82 ft)
SCSI Fast-20
-16 bit SCSI asynchronous commands with synchronous data transfer rates of up to 40 megabytes per second
Low Voltage Differential ( LVD)
-SCSI-3, Ultra 2 or Fast-40 SCSI-
High Voltage Differential (HVD)
Old interface
-SCSI-2, offering 25 meter (82 ft) cable length
-not compatible with LVD, but can be used together with expander
Straight Through used by all SCSI, which means that any SCSI cable will work (the pinout will match) as long as the connectors are the same on both ends
Internal and external connectors
50 pin D-shell, 50 pin Centronics SCSI-1
High-Density (HD)-SCSI-2
Very High Density Cable Interconnect (VHDCI)
-68 pins
Regular Density
-narrow Scsi
-50 pins
High Density
-SCSI-2
SCSI ID
Narrow-0-7
Wide-0-15
-host adaptor always gets 7
-best to set boot disk to 0
Set with jumpers
labeled: ID0, ID1, ID2 ... and so on
-binary system
-if ID0 is on, that's 1, if ID2 is on, that's 2, if ID3 is on, that's 4, and so on
combine jumpers for any combination of 0-7
General guidelines for SCSI Ids
-SCSI ids usually set by jumpers on internal peripherals
-usually set by switch on externals
-need not be sequential but adaptor and peripherals each must have seperate IDs
-7 has highest priority, best for controller
-next priorities in descending order 6-0, 15-8
-host cards usually preset to 7
-most internal Hard Disk preset to 0
Jumper Block/DIP switch settings
{SCSI Configuration Jumpers
-SCSI hard disks are equipped with much more sophisticated controllers than IDE/ATA drives
SCSI Device ID
-Narrow SCSI drives have a set of three jumpers
-used to assign the disk an ID number from 0 to 7
-wide SCSI drive has four jumpers to enable ID numbers from 0 to 15
Termination Activate
-If the hard disk is at the end of the bus, set this jumper
Disable Auto Start
inform the drive not to start automatically, wait for a start command over the SCSI bus
-saves power, sometimes set already
Delay Auto Start
-asks the drive to start automatically, but after waiting for a predefined number of seconds from the time power is turned on
Stagger Spin
-multiple drives asked to stagger starting times
Narrow/Wide
-control whether they will function in narrow or wide mode
Force SE
-Ultra2, Wide Ultra2, Ultra 160, Ultra160+ or other LVD SCSI drives to be forced to use single-ended (SE) operation
Disable Parity
-turn off parity checking of bus}
Termination
-Termination lets the Master device know that the end of the chain is reached so that it can stop sending commands.
-Termination is set by either a jumper or a dip- switch, much like IDs on most devices, unless device only has one connector and can't connect beyond that
-usually auto terminating
-some still need setting
Resolving ID Conflicts
Have manual handy
-First, ensure that the termination is set correctly and that the SCSI cable is in good working order.
-Disable the BIOS or BIOS scan for the SCSI ID.
-In order to disable BIOS, access the SCSI and then select the configuration utility by pressing Ctrl+A, when you are prompted during the boot process.
-Go to the Advanced Configuration Settings menu, scroll to find the BIOS Support for Int 13 Extensions option, and set the option to Disabled.
-Selectively disabling some performance-boosting options - Domain Validation, Packetized SCSI, and Quick Arbitration and Selection (QAS) may also improve the time necessary to complete a BIOS scan
Redundant Array of Independent Disks (RAID)
use for speed, increased storage capcity, fault tolernace
two types of RAID:
-Hardware RAID
-hardware based system
-handles RAID independent of host by sending across single disk per array to host
-host need not be aware of RAID subsystem
-External hardware solution SCSI--SCSI RAID
-Software RAID
an be configured and its setup can be done using an operating system
-lower performance than hardware
RAID 0- Data Stripping
-at least 2 disks, treated as 1
-splits data into chunks written across all disks in array
-fills first disk with data before going to second
-better transfer speed
-good performance both read and write
-entire storage capacity used
-not fault tolerant
-all data is lost in case of disk failure
RAID 1: Mirroring
At least 2 disks needed
-duplicates stored data on multiple disks
-excellent read speed
-if disk fails, data is not lost, replace failed disk, copy data from good disk
-effective capacity half of total capacity
-hot swap of failed disk not possible in software raid, best to use hardware
RAID 3
-striped and written on at least 2 different disks
-additional disk stores parity
-high data rate for read and write
-disk failures have insignifcant impact
-complicated
-Resource intensive with software
-low performance for random and minute I/O functions
RAID 5
Similar to 3
-minimum of 3 disks
-data transmitted by independent read and write operations
-larger data blocks written
-parity info found across all disks
-easier to implement with hardware than software
-fault tolerant
-read data very fast
-write data slower, due to parity calculation
-disk failure little impact on thouroughput
-complicated
-difficult to rebuild if disk does fail
RAID 10
combination of the benefits and the shortcomings of RAID 0 and RAID 1
-mirroring is done wherein all of the data gets stored on to a secondary disk
-Data transfer is accelerated by stripping across each set of disks
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Site Message
on Device Configuration And Ports