There are different slots and sockets for CPUs, and it is necessary for a motherboard to have the appropriate slot or socket for the CPU. Most sockets are square. Several precautions are taken to ensure that both the socket and the processor are indicated to ensure proper orientation. The processor is usually marked with a dot or a notch in the corner that is intended to go into the marked corner of the socket.
Sockets and slots on the motherboard are as plentiful and varied as processors. The three most popular are the Socket 5 and Socket 7, and the Single Edge Contact Card (SECC). Socket 5 and Socket 7 CPU sockets are basically flat and have several rows of holes arranged in a square. The SECC connectors are of two types: slot 1 & slot 2.
