At the heart of any laptop, PC, tablet or a mobile phone lies the motherboard. A motherboard is a printed circuit board (PCB) that anchors a communication between all the other components of the system. The Central Processing Unit (CPU), the memory, video card, sound card, and ports for peripherals etc are all unified by the motherboard either directly or via cables. It acts as a single stage to connect all of the parts of the system together and that truly justifies the name motherboard.

It is sometimes also referred to as a planar board, logic board, main circuit board or even a system board. But motherboard explicitly refers to a PCB with the expansion capabilities.


Before the 1980s, the digital computer constituted of multiple printed circuit boards with the parts connected by a backplane in a card-cage case. The CPU, memory, and peripherals were embedded on individual printed circuit board, which were secured into the sockets of the backplane. Later with advancement, the PC motherboards started coming with single ICs to support low-speed peripherals like keyboard, mouse, parallel ports, serial ports, and floppy disks drive.

Now let’s take a look at the complete advancement journey of the motherboard from 1980 to date.

Different Types of Motherboard

First Motherboard

The IBM Personal Computer featured the first motherboard in 1981, and named it ‘planar’. The motherboard held the computer’s CPU and RAM, provided ports for keyboard and cassette tape and also came up with audio and many more functions. It had the expansion slots for any add-on cards and also a system bus to handle the information flow.

AT Motherboards

In 1984, IBM came up with the Advanced Technology (AT) motherboard design. The board consisted of the advanced technology power connectors. Two power connectors of 6 pins each are housed on the AT motherboards. The AT form factor referred to the layout and dimensions of the motherboard. The AT motherboard was 13.8*12 inches, it means that it could not fit in the mini desktop or mini-tower cases.

ATX Motherboards

The ATX was the first significant motherboard development since the AT motherboard in the year 1984. The Intel released the new Motherboard ATX form factor in 1995. These ATX motherboards featured many improvements including new layout and dimensions, which improved the space. It overcame some of the prominent issues in the AT motherboard.

Micro ATX Boards

In the year 1998, the Micro ATX Boards were produced that despite being half the size of the standard ATX board were fully compatible. These were the first backward compatible boards and also supported more integrated peripherals. The Micro ATX boards were made to fit into smaller case PCs.

Motherboard Components

The Motherboard comprises various components of the computer system. It is good to know how the motherboard connects the various parts, to get a better idea about working of the computer system. Here we have elaborated a few of the typical parts of the motherboard. Take a look.

Central Processing Unit (CPU)

The Central Processing Unit is sometimes also referred to as the processor or the microprocessor. It is the part of the computer system that is subject to fetch, decode and execute the sets of instructions or programs. It is also responsible for handling arithmetic and logical operations. The CPU’s functioning heavily relies on the chipset, that is a group of microchips. For example, Intel Core i5, Pentium MMX or Intel 386 etc.

Random Access Memory (RAM)

Random Access Memory or RAM is a volatile computer memory, it means that the information stored is lost when the power goes off. It enhances the performance of the computer by storing the active programs and data. So that the processor can fetch those and do not have to look for it in the hard disk.


BIOS stands for Basic Input/Output system, its chief function is to handle the system setup process. It acts as an interface between the hardware and the operating system. The BIOS is stored on the ROM (Read Only Memory) chip on the motherboard.

CMOS (Complementary Metal Oxide Semiconductor)

The motherboards also come up with a separate block of memory made of CMOS RAM chips and are operated by the CMOS battery even when the PC is powered off. The CMOS RAM stores basic information about the PC’s configuration including the Plug and Play information, Date and time, RAM size, details about CPU, Power Saving settings etc.

Expansion Bus

It is an input/output pathway which allows information sharing from the CPU to the other peripheral devices. It includes a set of slots into which the expansion cards are inserted on the motherboard. PCI is the most commonly used expansion bus in PC and other hardware.

Computer Chipset

A chipset is a group of small circuits that handle the flow of data to and from the main components of the PC. The main components constitute the processor, the RAM, the secondary cache and any other device situated on the buses.

There are two main chipsets of a computer system:

  • The NorthBridge is responsible for managing the transfer of data between the CPU and the RAM. It is the reason why it is located near to the CPU.
  • The Southbridge also is known as an expansion controller handles the communication between slower peripheral devices.

Storage Connectors

Motherboards have the connectors for adding the storage devices like the optical drives, hard drives, and SSDs. These storage media communicates with the computer through the interface known as Serial ATA.

Power Connectors

The computers have a main power supply, but to distribute the power to all the components of it, power connectors are used. The power connectors divide the power from the main supply to the components like the RAM, CPU, expansion cards and chipset.

Operating Temperature

While the components of the computer system are working they tend to generate a lot of heat. The improper temperature may lead to poor performance and also reduces the life of the components. To overcome this, cooling fans and heat sinks are embedded to maintain the optimum temperature. The favorable operating temperature for motherboards is 45 degrees Celsius.


So that’s all about the motherboards. We tried to cover all the details about the motherboards from its types to the major components it comprises of. If we have skipped any of the major features, let us know in the comments section below. We’ll be happy to hear it from you.

Kindly rate your experience
[Total: 4 Average: 4.8]

Write a Comment