A CPU socket or CPU slot is a mechanical component that provides mechanical and electrical connections between a microprocessor and a printed circuit board (PCB). This allows the CPU to be replaced without soldering.
Common sockets have retention clips that apply a constant force, which must be overcome when a device is inserted. For chips with a large number of pins, either zero insertion force (ZIF) sockets or land grid array (LGA) sockets are used instead. These designs apply a compression force once either a handle (for ZIF type) or a surface plate (LGA type) is put into place. This provides superior mechanical retention while avoiding the risk of bending pins when inserting the chip into the socket.
CPU sockets are used in desktop and server computers. As they allow easy swapping of components, they are also used for prototyping new circuits. Laptops typically use surface mount CPUs, which need less space than a socketed part.
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