Motherboards, PC Cases, Power Supplies

The Motherboards (Mainboards) Used in Desktop PCs

MSI B450M A Pro Max socket AM4 mATX motherboard
MSI B450M A Pro Max socket AM4 mATX motherboard


1.Introduction to the desktop PC motherboard

2.How to identify a computer’s motherboard

3.Annotated Images of ATX Socket LGA775, Socket A and Socket 939 Motherboards (Mainboards)
—– Includes information on the new M.2 (m-dot-2) slot that is mostly used to install an SSD drive.

4.The motherboard’s chipset – the north and south bridges

5. –  The Level 1, Level 2 and Level 3 caches

6.Motherboard LED component-diagnostic lights and other motherboard diagnostic systems


POST: The motherboard being the cause of a slow M.2 SSD drive

POST: Steps you take to diagnose the dead  motherboard of a desktop PC

POST: Can I replace the motherboard of my PC without having to reinstall Windows 7/8.1/10?

POST: Upgrade your old computer with a motherboard, processor, CPU cooler, RAM memory bundle

POST: Upgrade Win7 PC: My Win7 computer running Windows 7 has become very slow. Should I upgrade it to Win10 or build or buy a new one?

POST: How to find out if a PC’s motherboard provides particular graphics card support

The information that this page provides – and related information

This section of this website provides detailed information on computer motherboards (also known as mainboards), the printed circuit board (PCB) that is the main component of a desktop or laptop computer. It covers how the motherboard integrates with the desktop-PC case, the power supply unit (PSU), the RAM memory, hard disk or SSD drive, optical CD/DVD disc drives and the subordinate PCB components, such as the graphics card and sound card – and the peripheral devices (USB devices such as external hard disk and optical drives, printers, flash drives, etc.) All of those PC components and peripheral devices have their own sections on this website under the Hardware menu.

Install a motherboard and power supply unit

Visit the Build Your Own PC section of this website for information on how to install a motherboard and power supply unit (PSU) in a PC case.

How to install a motherboard in the case & choices of processor & cooling units –

Motherboard and power supply problems and solutions

Problems are dealt with in the Motherboard and Power Supply Problems & Solutions section of this website.

PCI Express (PCIe) backwards compatibility

PCIe 4.0: What’s New and Why It Matters –

1. – “PCIe is also backward compatible. If you have a PCIe 4.0 graphics card [or a PCIe NVMe SSD] you can use it with a motherboard designed for PCIe 3.0; however, the card’s available bandwidth would be limited to the capabilities of PCIe 3.0. Conversely, a PCIe 3.0 card can fit in a PCIe 4.0 slot, but again it would be limited by PCIe 3.0.”

2 – Explaining PCIe Slots – The history of adaptor-card slots ending with PCI Express (PCIe), which is currently up to version 4.9. –

Information on what hardware and software is installed on a computer

If you need information on what hardware and software is installed on a computer, the Belarc Advisor from is a free tool (look under Free Download on its website) that identifies a Windows computer’s hardware (motherboard, graphics card, hard disk drive(s), DVD drive, etc.) and software (version of Windows, applications, etc.) and even software licences, including the Windows Product Key, which is always required when reinstalling Windows.

The miniaturised motherboards used in laptop computers are not dealt with in this article because they are only accessible by specially-trained technicians or people with the required know-how and, since they are not sold by computer stores, can’t be upgraded unless the upgrade is provided by the laptop’s manufacturer. You are stuck with the motherboard that is in a laptop computer unless it develops a fault and has to be replaced by its manufacturer with the same model of motherboard. However, second-hand laptop motherboards are being sold on auction sites such as eBay, but they may or may not be available for your make/model of laptop.



Detailed information on the PC case and power supply unit (PSU) is provided on the following sub-menu sections:

The PC Case –

The Power Supply Unit – PSU –

NEXT PAGEIntroduction to the desktop PC motherboard