Central Processing Unit and Cooling Systems May 2016 | Page 10

3. Registers
Registers are the temporary storage areas for instructions or data within the processor. Registers are basically special storage locations
somewhat similar to a computer’s memory though contained within the processor and exceptionally faster.
CPUs come in different form factors, each style requiring a particular slot or socket on the motherboard. Common CPU manufacturers
include Intel and AMD.
The CPU socket or slot is the connection between the motherboard and the processor. Most CPU sockets and processors in use today
are built around the architectures of the pin grid array (PGA) and land grid array (LGA), see pictures below. In a PGA architecture, pins
on the underside of the processor are inserted into the socket, usually with zero insertion force (ZIF). ZIF refers to the amount of force
needed to install a CPU into the motherboard socket or slot. In an LGA architecture, the pins are in the socket instead of on the
processor.

The CPU executes a program, which is a sequence of stored instructions. Each model of processor has an instruction set, which it
executes. The CPU executes the program by processing each piece of data as directed by the program and the instruction set. While the
CPU is executing one step of the program, the remaining instructions and the data are stored nearby in a special memory called cache.