What Are the Main Components of a Computer System?

We all know that computers are complex devices, machines made out of an amalgam of electronic parts and components. But which computer components are essential for a computer to run? Modern PCs can still function fully without Bluetooth or a floppy disk drive. Here is a list of computer components that a computer system cannot do without.

* Motherboard

The motherboard is a very basic unit in any computer system. This is the computer component to which all other internal computer components are attached. It links all the other main components of a computer system together. Consequently, motherboards are sometimes referred to as the “heart” of a computer system.


The central processing unit or CPU is the computer component responsible for running programs and applications on the computer. Without a CPU in your computer, you will not be able to do any tasks — you cannot boot to an operating system, you cannot play music, videos and games, and you cannot do any word processing. For a computer to function, it has to have a CPU.


Random Access Memory or RAM is another vital computer component. It is the storage media where a computer temporarily stores files and information that it can pull at random when running programs and applications. Together with the CPU, RAM determines the computer’s speed. A computer with a large RAM and a mediocre CPU can actually run faster than a computer with a powerful CPU but low RAM.


As opposed to the RAM, the hard disk drive or HDD stores computer files and data long-term. Even without power, the hard drive still retains the files stored inside it. The hard drive can store important system files like the operating system, program files and other data. It can also be used to store mp3s and videos. If the computer runs out of RAM, it will temporarily use the hard drive as a virtual memory bank.

* Video Card

A video card allows a computer to display images on the computer monitor. It helps speed up the rendering of images onscreen and contributes to clearer and detailed pictures. PC gamers and multimedia software users will find a high-end dedicated graphics card helpful in running graphics-intensive programs smoothly.


The power supply unit or PSU supplies all computer components with power. It converts the high voltages from an AC power outlet to lower voltages that are safe for internal computer components. Without a PSU, a computer and its components will not be able to power up.

A computer can also benefit from an optical drive to read and play CDs and DVDs, a network card and router for connecting to the Internet, and peripheral devices such as printers and scanners. The motherboard, CPU, RAM, HDD, video card and PSU are, however, the main components that make up a computer system.

Leave a Reply