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Components of a CPU

Do not be confused. In this article, I am discussing only the hardware components of a CPU. That is, the various parts you notice inside the CPU case. These are the hardware used inside the CPU case, whom I am referring to here as a “Parts of computer CPU” or “Components of a CPU”.

The different components of CPU perform the various task inside the CPU case. Without these components, a computer system is useless.

The following are the components of a CPU

  1. Motherboard
  2. Processor
  3. RAM
  4. HDD
  5. CD/DVD drive
  6. FDD
  7. SMPS
  8. Expansion card
  9. Bus cable
  10. Cooling Fans


best motherboard

It is the main circuit board of a computer system. The motherboard is the main interface to connect different parts used in the computer system. The motherboard is a printed circuit board (PCB). All input/ output devices, as well as other essential components of the computer system, are connected with the motherboard. 

Sometimes, a motherboard is known as a logic board. The term “logic board“, is used by Apple for its Macintosh computer.

The manufacturer produces varieties of motherboard for a computer system. These motherboard sizes and shapes are different, that is, known as form factor. There are different types of motherboard form factors on the market. 

  1. Standard ATX
  2. Micro ATX
  3. Mini ITX
  4. BTX
  5. Mobile ITX
  6. Pico ITX

Nowadays, the most desktop computer uses the ATX form factor motherboard. 

Processor or CPU

It is the most necessary component of a CPU. Generally, you know this component as the brain of the computer. The processor or CPU executes a set of instructions within the computer to complete its task. A processor performs basic arithmetic, logic operations. It also performs I/O operations and controlling various instructions set inside the computer.

The general term of the processor is “CPU”. The processor or CPU is a small chip which, resides inside the computer or other electronic devices.

Note: You should not confuse with the term “CPU”. Traditionally CPU term represents the “processor” or “microprocessor”. Most of the time, we use to call “CPU case” as “CPU” only. Check the following diagram.

CPU case and CPU

Nowadays, the desktop computer uses Intel and AMD CPU. These modern computers have multiple cores in a single chip. (Example, dual-core, quad-core, octa-core, etc.)

The Clock speed, as well as the number of cores, defines the processing speed of a processor. A multiple core processor can easily handle different tasks at a time. With a multi-core processor, the hyper-threading technology of the processor increases the PC performance.

The processor clock speed determines the execution speed of the processor. More clock speed means faster execution time. The processor clock speeds measures in Gigahertz (GHz).

Some examples of Intel processors: Intel Pentium dual-core processor, Intel i3 processor, Intel i5 processors, Intel i7 processors.

Examples of AMD processors: AMD A4, AMD A6, AMD A8, AMD A10, etc.

RAM (Random Access Memory)


RAM is the main memory of a computer system, which is also known as primary memory. It is short-term memory. A Ram cannot store data permanently on it. Therefore, RAM is temporary memory. To store information or data on the Ram, it needs continuous power. If there is no power, RAM automatically clears all the data, that is, stored on it.

There are two types of RAM. One is Static RAM (SRAM), and the second one is Dynamic RAM (DRAM).

In modern computers, manufacturers use Synchronous Dynamic Random Access Memory (SDRAM). DDR4 is the latest SDRAM version used on the computer. DDR4 is faster than the previous versions, such as DDR3, DDR2, etc. DDR full form is “Double Data Rate”.

HDD (Hard disk drive)

Already you are familiar with this part of the computer CPU. HDD is a magnetic storage device, which is also known as a permanent memory. It is a non-volatile memory, which retains data even after power off.

The primary feature of HDD is its storage capacity and performance. The storage capacity of HDD measures in Gigabyte (GB) or Terabyte (TB) (Example, 1TB, 500GB,…).

Now a day, SSD (Solid State Drive) becomes the first choice of permanent memory for computer users. SSD is a flash storage device, which has a higher data transfer speed than the magnetic HDD. But SSD is more expensive than the traditional HDD.

CD/DVD drive (Compact Disc/Digital Versatile Disc)

It is an electronic device used on a computer. The CD/DVD drive uses to read and write data on Compact Disc (CD) or Digital Versatile Disc (DVD). This drive is also known as an optical drive.

You can store a maximum of 700MB data on a CD and either 4.7GB or 8.5GB on DVD.

FDD (Floppy Disk Drive)

IBM invented the first floppy disk. The FDD uses to read and write data on a floppy disk. A Floppy disk is a magnetic storage medium, as well as the storage capacity, which is very low.

In a modern computer, you cannot see any FDD. Manufacturers do not install FDD on modern PCs. Now, FDD is removed from the computers by other storage devices like a USB drive.

SMPS (Switch Mode Power Supply)

 It is another most necessary component of a CPU. Manufacturers use different electronic devices inside the CPU case, as well as these electronic parts need the power to function. Hence, SMSP is used to supply power to the various parts of the computer.

The SMPS supplies DC voltages to the other part of the computer system. It converts high voltage AC to the low voltage DC.


In a general computer, SMPS supplies DC voltage to the motherboard, HDD, CD/DVD drive, and FDD.

Expansion Cards

Expansion cards are known as the internal cards, add on cards, and so on. It is an electronic circuit board. An expansion card helps to increase the functionality of a computer in a specific field. A video card or graphics card enhance the display performance of a computer system.  

Some common types of expansion cards are a graphics card, sound card, network card or NIC, modem card, etc.

Bus cables

In the computer, the term “bus” means a path to transfer data from one place to another. On a computer, you can find two types of bus cable, SATA and PATA. Bus cables help to transfer data between the motherboard and hard drive or CD/DVD drive.

sata pata cable
sata pata cable

 SATA – Serial Advanced Technology Attachment

 PATA- Parallel Advanced Technology Attachment

Cooling Fans

These are another essential component of a CPU. Cooling Fans protect your computer from overheating problems. By providing cold air to the CPU case and processor, cooling fans cool down computer temperatures.

You can find two cooling FANs inside a general CPU cabinet, Rear/Sys Fan and CPU Fan.

CPU fan SYS fan
CPU fan SYS fan

Rear/Sys Fan provides cold air to the CPU case.

CPU Fan uses to cool the CPU heat sink.

If you have the overheating issues on your computer, then you can check these techniques to cool a computer or laptop.


Parts of computer CPU are essential for a computer system. The knowledge of components of CPU helps to perform the assembling process of a computer system with ease. I wish you have gained the basic ideas of various components of a CPU.