Computer Motherborads

Computer Motherboards

A computer motherboard is the piece of hardware which all the other hardware components connect to. It also handles the computer's initial boot-up sequence (known as the BIOS).
Motherboards are also commonly referred to as the main board (and on Apple systems, the logic board). They're also sometimes referred to as the mobo. There are different sizes of motherboards, the most common of which is the ATX motherboard which is 305 x 244 millimeters.
ATX was first introduced in 1995 and whilst there have been pushes to move away from ATX motherboards, it is still the most popular size.
A smaller standard also exists, known as micro ATX motherboards. These are 244 x 244 mm in size and they are intended to be used in smaller systems. A motherboard usually can house just one CPU (the 'brains' of a computer; its computational centre).
However it is possible to get dual processor motherboards, which are used mainly in higher end systems (such as servers) where a greater amount of processing power is required.
For further information on various types of motherboards, check the list below for various articles in this section.

Motherboard Diagrams In Detail

A motherboard can be a very confusing looking component. This is because various hardware parts, connectors and power cables connect to it.
Amongst other things, it has a large panel of I/O connections, expansion slots (PCI and PCI-express), a chipset, various drive connectors, memory slots, power inputs, a power delivery unit, a processor slot and more!
Hence it is not surprising that many people find a motherboard to be confusing.
As a result, this article will show a labeled computer motherboard diagram and describe the various important parts of a motherboard. To get started, check-out the diagram below.
It has various numbers on it next to the most important parts (it won't cover all parts, but it'll cover the main and most common ones). Then see the numbered list below the diagram for a description of what each part is or does.
The motherboard being analyzed is the Gigabyte GA-P55M-UD2, a popular motherboard for the Intel Core i3 and i5 range. Many motherboards have very similar components and layouts though, so the exact motherboard being analyzed doesn't really matter.
Numbered motherboard diagram
  • Rear I/O - These are the external ports, for example the USB and other I/O (input/output) ports). The monitor, keyboard, mouse and speakers (along with other peripherals such as a printer) will slot in here. Despite appearing as though you are plugging these devices into the case, you are actually plugging them into this external part of the motherboard.
  • Power Input - Most motherboards are powered by a 24-pin ATX connector (see 12, below). However some modern motherboards require some extra power (especially for the CPU), hence this 8-pin power connector.
  • PCI Slots - These two light coloured components are the PCI slots. They are usually used to insert extra hardware components which are less powerful (in short, which have a lower data transfer/bandwidth rate than components which require a PCI-express slot). Examples include sound cards, modems and ethernet (network) cards.
  • PCI Express Slot - These two blue components are the PCI-Express slots. They have a higher data transfer/bandwidth rate than PCI slots and thus are used by higher-powered hardware parts such as a graphics card.
  • Battery - A motherboard holds various information about the system's configuation, along with the date and time. It is important that this data isn't lost even when the computer is switched off, hence this battery is used which ensures that such data doesn't get lost when the computer is turned off.
  • Processor - Once the lever is lifted, the CPU (the 'processor' - the 'brains' of the computer, i.e. where instructions are carried out and calculations are performed) is put into this socket. The CPU gives off a large amount of heat, and as a result a heatsink is installed over it (the four holes in all four corners of the CPU socket helps with the installation of certain heatsink's/CPU coolers).
  • Chipset - The chipset connects all the components on a motherboard and allows them to share data. As CustomPC (a magazine in the UK) says, "If the CPU is the brain of your PC then the chipset is the nervous system".
  • Memory/RAM Slots - These slots are where you install the memory/RAM sticks into your motherboard. They tend to be color coded because there's a certain order you should insert memory sticks depending on how many sticks you have.
  • USB Cable Slots - Many computer cases come with USB ports in the front. These are not part of the motherboard (unlike in 1, above) and so they need to be inserted into the motherboard - hence these slots.
  • Front I/O - Computer cases also come with various LEDs (lights showing hard-drive activity, for example) along with reset and power buttons. These also need to be connected to the motherboard, hence these cable slots.
  • Drive Connectors - This is where the various drives connect to your system. These include your hard-drive(s), optical drive(s) [for example CD/DVD drives] and - if you have a modern computer - solid-state drives (a newer, faster data storage device than hard-drives).
  • Power Input - This is the 24-pin ATX connector (as mentioned in 2, above). This is the main power connector for a motherboard and it powers much of the components attached to the motherboard (along with the electrical components - such as the chipset - on the motherboard itself). The 24-pin ATX connector comes from your computer's power supply unit (PSU).
Motherboard standoff screws are usually coarse threaded screws which allow for the motherboard to be installed/put into the computer's case.
The most common type of standoff is a brass hex-shaped standoff screw and it can be installed using a hex driver tool, although they are usually relatively easy to screw in using your hands. Another type of standoff is one with a clip style that snaps into the case's tray.
Standoff screws are necessary because the motherboard couldn't simply be screwed directly into the computer case (this is because the case is metal, and if the motherboard touched this metal case it would cause a short-circuit and possibly damage some of the computer's components).
Hence standoffs are used to create a buffer between the case and the motherboard, and thus allowing for the motherboard to be inserted into the case in a safe way.
The image below shows the two standoffs described above. The brass standoff screw (left) is fairly common, although the clip-style one (right) is still used - albeit less commonly - today:
The two main types of motherboard standoff screws

Installing Motherboard Standoffs

The brass motherboard standoffs (or the clip-style ones) are screwed into the computer's case in a way that lines up with the motherboard. You can determine where these holes are by looking at the motherboard - it will have holes in particular places (please note that the four holes around the CPU socket are not applicable; these are to install the CPU heatsink/cooler). Using this as a reference, determine where the standoff screws need to be placed in the computer case.
Screw (or clip) the standoffs into the case's tray. Once this is complete, carefully lower the motherboard into the case and insert it through the standoffs, being careful not to touch the case with the motherboard. Once this is complete, use the actual (non-standoff) screws provided to screw the motherboard into the standoffs. Do this gently since you do not want to damage the motherboard.
This is pretty much all that is required to install the motherboard standoffs and hence the motherboard into the computer case.

Gaming Motherboard

A motherboard is the piece of computing hardware which is central to your computer system, since all the other hardware parts link up to it.
And whilst many people naturally focus on the processor, RAM and graphics card when building a gaming desktop computer, the motherboard shouldn't be overlooked.
This is because - as mentioned earlier - it is central to your computer system, and thus buying a good quality motherboard is essential.
In addition, if you plan on overclocking your CPU, the choice of motherboard is absolutely essential since some motherboards have wildly varying amounts of support and features for overclocking.
Some motherboards just have some very basic features to help you overclock, whilst other motherboards are designed with overclocking in mind.
Hence this article will cover four of the best motherboards to be used in gaming systems; two of which are for AMD processors, and two of which are for Intel ones.

1) Gigabyte GA-P55M-UD2

This motherboard retails for around $105 and it is a great Intel motherboard, especially for the Core i3 and i5 ranges. It has a good number of features and expansion slots, and its overclocking interface/features in the BIOS are pretty well laid out.
Gigabyte GA-P55M-UD2

2) MSI 770-C45

The MSI 770-C45 is perfect for a budget gaming build, retailing at $80. It supports the AMD Athlon II X2 processor range and comes with a decent range of features and slots for the price. It also provides pretty good support for overclocking.
The MSI 770-C45 motherboard

3) Asus P6X58D-E

This is a premium motherboard, aimed at the highest end gaming machines. It is best suited to the Intel Core i7 range, and it retails at $220. It has a large number of features, slots and overclocking capabilities; as you would expect from such a board. The Gigabyte X58A-UD3R board is also fairly evenly matched to this Asus board, so consider that one too as a potential alternative. A picture of the Asus board follows:
Asus P6X58D-E motherboard

4) MSI 890FXA-GD70

This is another premium motherboard, retailing at $200. It comes with a large number of PCI-Express slots, allowing for up to 4 graphics cards to be installed! (Which is especially useful if you're into high CPU/GPU processing power for projects such as Folding@home). Naturally this board also comes with the full range of features and overclocking capabilities.
MSI 890FXA-GD70 motherboard