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What is a motherboard and how it works

Building a PC and need a little help? We answer your motherboard questions.


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Whether you’re building a PC or buying one, there’s a lot you’re going to need to know about hardware – so we’ve created a series of mini-guides to answer your questions and to break down computing jargon in a way that anyone can understand.

One component that plays a central role are motherboards. Often referred to as the heart of a computer, the motherboard is an essential piece of hardware that connects and powers various components, allowing them to work together. In this article, we'll tell you everything you need to know about motherboards, exploring what they do, how they work, their components and upgrades, form factors, and much more. So, let's get started!

What does a motherboard do?

The motherboard is a vital bit of kit that acts as the central hub, connecting up all the other hardware components within a computer. It’s a platform for essential components such as the CPU (Central Processing Unit), GPU (Graphics Processing Unit), RAM (Random Access Memory), storage devices and lots of peripherals. The motherboard acts as a bridge that carries data and power between different parts of the computer, meaning smooth operations and powerful performance.

How does a motherboard work?

The motherboard contains lots of pathways called traces. These traces allow electrical signals to travel between different parts of the motherboard, allowing the CPU, RAM, and other hardware to communicate and share data.

The motherboard contains a BIOS (Basic Input/Output System) or UEFI (Unified Extensible Firmware Interface), which acts as a firmware responsible for kick starting hardware during the boot process and giving you a dashboard where you can adjust system settings.

Where is the motherboard located?

The motherboard is mounted inside the computer case. It lies horizontally at the bottom or vertically along one side of the case, depending on the design of your case. The motherboard is secured to the case using screws and standoffs, so it doesn’t make contact with the metal case - reducing the risk of electrical shorts.

Motherboard components

A motherboard is composed of several key components that work together to makes sure your computer functions the way it should. The main components of a motherboard include:

CPU Socket

This is where the processor is installed and connects to the motherboard, providing the brainpower for the computer.

RAM slots

These slots are the place to put your computer’s memory – which provides temporary storage for data the CPU is actively using.

Expansion slots

Whether you want to upgrade your PC’s graphics or sound, these slots allow for additional hardware components like GPUs, sound cards and network cards.

Storage connectors

The motherboard features connectors such as SATA and M.2. These allow for the attachment of storage devices like hard drives and SSDs.

Power connectors

These connectors supply power from the PSU (Power Supply Unit) to the motherboard and its components.


This chip stores the firmware that takes care of booting up the computer during start up and giving you a display where you can adjust system settings.

CMOS battery

The CMOS battery powers to the BIOS/UEFI chip, keeping system settings where you left them and allowing the real-time clock to run when the computer is powered off.


The chipset manages the flow of data between the CPU and other components.

Motherboard form factors and types

Motherboards come in various “form factors.” Form factors just refers to the different size, shape, and mounting points of the motherboard.

Common form factors include ATX, Micro-ATX, Mini-ITX and Extended ATX (EATX). Each form factor is built with a different type of computer in mind. Often, it’s just to do with how much physical space there is within each case within the case.

So, a standard-sized tower home PC will probably have an ATX motherboard – which can offer space for upgraded graphics cards and is the choice of most gamers. Whereas Mini-ITX motherboards are made for much more compact desktop PCs – prioritising space over more memory and extra hardware.

Connecting a motherboard

When building a computer, hooking up the motherboard properly is essential. It involves very carefully inserting the CPU into the designated socket on the motherboard. At this point the motherboard can be inserted into its PC case and secured with screws and stand offs.

Next, the RAM modules are put into the right slots on the motherboard, followed by connecting up storage drives and attaching expansion cards to their respective slots. Finally you need to make sure that all power connectors are correctly plugged in before you can power up your PC.

Motherboard Frequently Asked Questions

How can I find motherboard model information?

If you're unsure about the model and specifications of your motherboard, there are several ways you can find out.

1. Check the motherboard's box or manual if you have them.

2. Use system information tools on your computer, such as "System Information" on Windows or "About This Mac" on macOS.

3. Open your computer case and check the motherboard for model markings.

How many GPUs can a motherboard support?

The number of GPUs (Graphics Processing Units) a motherboard can support depends on its design and the number of available PCIe (Peripheral Component Interconnect Express) slots.

High-end gaming motherboards often feature multiple PCIe x16 slots, allowing for many GPUs to be installed. This configuration is called an SLI (Scalable Link Interface) for Nvidia GPUs or CrossFire for AMD GPUs. However, not all motherboards support multiple GPUs, and some may only have a single PCIe x16 slot.

How many hard drives can a motherboard support?

The number of hard drives a motherboard can support depends on the available storage connectors. Motherboards typically have several SATA connectors and may also offer M.2 slots for faster NVMe SSDs.

The number of SATA connectors varies based on the motherboard's design and can range from 2 to 8 or more. Some high-end motherboards may include additional storage options like U.2 or additional M.2 slots, allowing for even more storage devices to be connected.

How many memory modules are installed on the motherboard?

The number of memory modules that can be installed on a motherboard depends on the number of RAM slots it has. Common configurations include motherboards with two, four, or even eight RAM slots.

The maximum amount of RAM a motherboard can support depends on its chipset and the type of memory used – whether that’s DDR3, DDR4 etc. For the best performance, you have to install memory modules in matched pairs (dual-channel) or groups of four (quad-channel).

How many motherboard standoffs do I need?

The number of motherboard standoffs required depends on the form factor of the motherboard and the specific case being used.

ATX motherboards typically require 6-9 standoffs, while Micro-ATX and Mini-ITX motherboards may need fewer due to their smaller size.

How many ohms can my motherboard handle?

This is a misconception, since motherboards aren’t rated in terms of ohms, as ohms are a unit of electrical resistance used for specific components like resistors.

However, motherboards are designed to handle varying amounts of current and voltage based on the specs of their components. It’s crucial to provide the correct power supply to the motherboard and its components to prevent damage or instability. So check that your power supply is compatible with your motherboard.

How many PCI slots does a motherboard have?

The number of PCI slots on a motherboard can vary depending on the specific model and form factor. Generally, motherboards have between one to four PCI slots, allowing you to expand your system with various peripherals like graphics cards, sound cards or network adapters.

Always check the specifications of your chosen motherboard to make sure it fits with how you plan to use your PC.

How many SATA connectors are on a motherboard?

Motherboards typically offer multiple SATA connectors, which are used to connect storage devices such as hard drives and SSDs. The number of SATA connectors can differ based on the motherboard's design and intended use.

Commonly, you'll find between four to eight SATA connectors on modern motherboards, but high-end boards may offer even more – giving you the ability to connect more storage devices.

How many SSD can the motherboard support?

The number of SSDs a motherboard can support depends on the available SATA connectors or M.2 slots. Some motherboards might have multiple SATA connectors, allowing you to connect several SSDs.

Many modern motherboards feature M.2 slots, which support even more SSDs. Always check your motherboard specs if you plan to use more than one SSD.

How many USB ports does a motherboard have?

Motherboards usually come equipped with a range of USB ports to connect lots of different devices. The number of USB ports can vary depending on the motherboard's make and model.

Generally, you can expect to find between four to eight USB ports on a standard motherboard. However, some gaming or high-end motherboards might offer even more USB ports.

When was the first motherboard invented?

The concept of a motherboard first came about in the mid-20th century when early computers started to take shape. However, the motherboard that resembles what we know today was developed in the early 1980s.

IBM's introduction of the IBM PC in 1981 established the principles and design of modern motherboards. Over the years, motherboard technology has evolved, leading to the wide range of motherboards available today.

Hopefully, this article has helped you get to grips with what a motherboard is and how vital they are for PCs, Macs and laptops. We’re here to help you build a gaming PC and our tech experts are happy to answer your questions with our 24/7 tech support.

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