What is a CPU?

What is a CPU?

The CPU (Central Processing Unit), or sometimes known as processor, is one of the most important component in a computer system. Being the brain of the computer system, its task is to take care of all the data calculation and make sure they are processed in the fastest time possible.

CPU is not something you can see from the outside of the computer. In fact, you won’t be able to see the CPU on a fully-assembled PC. To see it, you have to remove the computer casing, unplug the wire and remove the heatsink (and fan), only then can you see the surface of the CPU. The shape of the CPU is a small square chip with lot of connector pin underneath.

The images below show the back and the top of a CPU.

Back of CPU	Top of CPU

How CPU works

How a CPU works is actually very simple and can be illustrated with the following 3 steps:

1. When you click to execute an application, the raw instruction is first fetched from the hard disk (sometimes from the memory) and sent to the CPU for processing.
2. When the CPU receives the instruction, it will execute the logic and compute the result.
3. Once the CPU finishes processing, it will send the result to the respective device to output to the user.

While it may seems easy, all these 3 steps must be completed in a split second. Delays in any of these steps will result in a lag in the computer, which we do not want it to happen on our gaming computer at all.

Therefore, to improve the performance of the computer, it is not enough to have a fast CPU, you still have to ensure that the transfer of information to the CPU are done in the shortest time.

The next page will discuss the factors that affect a CPU performance.