CPU

If you consider your brain to be the most important part of your body, then its counterpart in a computer is its CPU. The central processing unit is the computer component that reads a command from the user and instructs the HDD or the hard disk drive to load the corresponding command into the computer’s memory.

When a user enters a command through a keyboard or other input devices, the CPU processes such a command and fetches data as copied from storage media (often an HDD). Register is a type of memory used by the CPI in such a process. The CPU makes extensive use of wires or cables to communicate with the computer’s memory cells.

Some additional traces of memory are also need to carry the signals as the CPU is in the process of reading or writing. In most cases, the CPU is only capable of holding minimal amounts of data at a certain time, which are held in a temporary storage space referred to as a cache.

It is crucial for the CPU to keep track of the commands being executed, so it makes use of program counters, special CPU registers that keeps a record of the addresses of the commands being executed. In other words, the CPU organizes things to their proper places just like you would put files in different file folders.

The central processing unit is in constant need of providing the memory address with a file so the computer, and ultimately the user, can access such a file. This means that the CPU still has to fetch such a file after locating it in the storage media. Hard drives can be very slow as storage media, especially in contrast to RAM.

The maximum data transfer rate of RAM is much higher than a hard drive, but a CPU’s processing speed is still four to five times faster. Cached RAM, on the other hand, can usually come close to the speed of your CPU. In the end, though, it is primarily the speed of your CPU that will determine the overall performance of your PC.