A central processing unit (CPU) is the electronic circuitry within a computer that carries out the instructions of a computer program by performing the basic arithmetic, logical, control and input/output (I/O) operations specified
Alternatively referred to as the brain of the computer, processor, central processor, or microprocessor, the CPU (pronounced as C-P-U), short for Central Processing Unit, was first developed at Intel with the help of Ted Hoff in the early 1970’s. The computer CPU is responsible for handling all instructions it receives fromhardware and software running on the computer.
Note: Many new computer users may improperly call their computer and sometimes their monitor the CPU. When referring to your computer or monitor, it is proper to refer to them as either the “computer” or “monitor” and not a CPU.
The picture below is an example of what the top and bottom of an Intel Pentium processor looks like. The processor is placed and secured into a compatible CPU socket found on themotherboard and, because of the heat it produces, it is covered with a heat sink to help keep it cool and running smoothly.
As you can see in the above picture, the CPU chip is usually in the shape of a square or rectangle and has one notched corner to help place the chip properly into the CPU socket. On the bottom of the chip are hundreds of connector pins that plug into each of the corresponding holes in the socket. Today, most CPU’s resemble the picture shown above; however, Intel and AMD have also experimented with slot processors that were much larger and slid into a slot on the motherboard. Also, over the years there have been dozens of different types of sockets on motherboards. Each socket only supports specific types of processors and each has its own pin layout.
Components of the CPU
In the CPU, the primary components are the ALU (Arithmetic Logic Unit) that performs mathematical, logical, and decision operations and the CU (Control Unit) that directs all of the processors operations.
Over the history of computer processors, the speed (clock speed) and capabilities of the processor have dramatically improved. For example, the first microprocessor was the Intel 4004 that was released November 15, 1971 and had 2,300 transistors and performed 60,000 operations per second. The Intel Pentium Processor pictured above has 3,300,000 transistors and performs around 188,000,000 instructions per second.
Types of CPUs
Below is a list of the more common types of CPUs for home or business computers, in chronological order of release by manufacturer.
Note: There are multiple versions for some of these CPU types.
Mobile Athlon 64
Athlon 64 FX
Athlon 64 X2
Turion 64 X2
Pentium w/ MMX
Mobile Pentium 4-M
|Pentium Extreme Edition
Core 2 Duo
The AMD Opteron series and Intel Xeon series are two common types of CPUs for servers and some workstation computers.