Motherboard Sizes

Motherboard Sizes


Martha Davis
August 20, 2021

Are you planning to build a PC? Then, you might want to consider choosing the correct motherboard that fits your needs.

The motherboard is the heart of the PC and helps in its smooth and efficient operation.

So, the motherboard that you choose affects the PC’s performance.

Picking the correct motherboard for your PC is by no means an easy task. You have boards that come in all sizes and shapes.

However, one of the crucial aspects that you need to look at when choosing a motherboard for your PC is the size or form factor.

Motherboard Form Factors

As suggested earlier, motherboards come in all sizes. You have boards that are minuscule, and you also have huge boards. Typically, motherboards are of seven types depending on their form factors.

ATX Form Factor

ATX Form Factors

ATX motherboards should be your choice, especially if it’s the first time you build a PC. These boards come in sizes of 12 by 9.6 inches. So, this means that you can make a mid-tower or tower PC on top of them without any trouble. Also, it is much easier to find an ATX motherboard as compared to the other types.

Moreover, considering the size of an ATX motherboard, you can also ensure that they come with lots of heat sinks. Besides this, you can always use several graphics cards at once since they have at least two or four PCIe slots.

In terms of RAM slots, ATX motherboards have at least four DIMM slots with dual- or even quad-channel memory support.

However, though ATX motherboards boast several advantages, they also come with a few drawbacks. For instance, they are unsuitable for a small PC enclosing and are a tad bit expensive than their smaller counterparts.

E-ATX Form Factor

E-ATX Form Factor

 Considering the pros and cons of ATX motherboards, you could also step up the game by going for an E-ATX motherboard.

The term ‘E-ATX,’ when expanded, translates to ‘Extended ATX.’ These motherboards come in sizes of 12 by 13 inches and are slightly larger than ATX motherboards.

You can expect the same features here, but since E-ATX motherboards have more room, they usually come with additional slots and heat sinks.

Besides this, you can these boards also have more RAM slots. In fact, some E-ATX motherboards even have up to eight RAM slots and two CPU sockets.

Having two CPU sockets means that you can use two processors at once rather than a single processor.

However, do note that they are harder to find than their ATX counterparts.

XL-ATX Form Factor


XL-ATX motherboards come in sizes of 13 by 10.4 inches and are easy to find, although they may be more expensive than Standard ATX boards.

However, despite their bigger sizes, they don’t offer any significant advantages over their ATX or E-ATX counterparts.

Besides, with the power of ATX and E-ATX motherboards increasing, the need for bigger motherboards such as the XL-ATX is slowly going away.

But you can still get one, especially if you are building a powerful gaming machine that needs more PCIe slots.

Micro ATX Form Factor

micro atxs

Micro-ATX motherboards are trimmed-down versions of ATX motherboards. These boards have similar configurations as ATX motherboards, except that their smaller sizes don’t allow too many slots.

Here too, you get four RAM slots if you buy a high-end model, although, in most cases, they come only with two slots.

Barring this, you get all the other aspects, except that you won’t expand the RAM or install a more powerful graphics card.

Also, due to their sizes, Micro ATX boards tend to be less expensive than ATX or E-ATX boards and fit in smaller PC cases. The only drawback is that you won’t overclock your PC or build a more powerful one.

Mini ITX Form Factor

Mini ITXs

Mini ITX motherboards are among the smallest boards on which you can use standard hardware components.

The sizes of these boards are usually 6.7 by 6.7 inches, so getting more heat sinks or a larger VRM section is a rarity. Also, since these boards are small, they cannot house more than two RAM slots.

Also, note that you can’t build a powerful multi-GPU PC with these boards.

However, if you are looking to build a compact PC or one that doesn’t occupy lots of space, then using Mini-ITX motherboards would be ideal.

Nano ITX Form Factor

Nano ITX Form Factor

At only 4.7 by 4.7 inches, Nano ITX motherboards are smaller than even Mini-ITX boards. However, one of the primary advantages of these boards is that they consume less power.

That said, you cannot fit standard components into a Nano ITX motherboard, and such boards are suitable only for building entertainment systems, such as smart TVs or those used in movie theaters.

Pico ITX Form Factor

Pico ITX Comparison

 As the name suggests, Pico ITX boards measure only about 3.9 by 3.9 inches and are smaller than Nano ITX motherboards. Such boards are perfect for industrial automation and other such devices since they consume less power.

Where are Motherboards of Different Form Factors Used?

Motherboards of different form factors find varied uses.

For instance, you can build a workstation or desktop PC using a Standard ATX board, whereas you can build a more compact PC with a small form factor with Micro and Mini ATX boards.

Similarly, Nano ITX and Pico ITX boards allow you to build embedded systems.

Likewise, different systems with motherboards of varied form factors housed inside them find uses in other places. Some typical applications of motherboards of varying form factors include:

In-Vehicle Computer Systems

Intel Atom x7 E-3950s

In-vehicle computer systems use Mini-ATX motherboards due to their small form factors. These systems can run several real-time tracking and other such monitoring applications.

One of the best examples of an in-vehicle system that uses a Mini-ATX motherboard is Lanner’s V3G.

The V3G houses an Intel Atom x7 E-3950 chipset. The Intel Atom SoC present inside this system consumes less power and is a decent upgrade over the previous generation Atom processors since it is a 14nm fabrication process.

The Mini-ATX board used in the V3G consists of two mini-PCIe slots with swappable SIM support.

So, this means that you can insert a SIM card that supports 3G/4G/LTE cellular connectivity.

Besides this, the Mini-ATX board present in the V3G also has two serial COM ports, video output by DVI-D ports, USB and Digital I/O ports, and RJ-45 LAN ports, not to mention options for SATA/ mSATA storage. So, that’s a lot of ports considering the size of the board.



Motherboards of different form factors also find uses in various IoT devices, particularly those used for smart street lighting.

Countries across the world are moving towards smart street lighting by adopting technologies such as IoT. These IoT-enabled street lights consist of various sensors, wireless communication points, and other such open-interface technologies.

So, suppose you want to get these lights to work correctly. In that case, you also need to consider external environment factors, which is why they need lots of I/O ports, LTE Connectivity, and Wide Operating Temperatures, besides a small form factor.

Compact industrial-grade box PCs are best suited for these devices since they are small and occupy less space. Their operating temperatures can also be as low as -40 degrees Celsius and as high as 70 degrees Celsius. Besides this, they also come with lots of dedicated ports, LTE connectivity, and more.

How To Choose The Right Motherboard Form Factor For Your PC?

ITX Portable PCs

The type of motherboard you will need depends on the kind of PC you are building and what you intend to use it. For instance, if you are looking to use your PC for work in a home office set up, you may build yourself a PC with a Mini ITX board consisting of a GPU that allows you to do some intensive tasks while keeping things compact.

However, while building a compact machine looks ideal for a home office environment, the process can be cumbersome for rookies.

So, if you are inexperienced at building PCs or your first time, you can always go for an ATX motherboard since it is easier to install and powerful. Also, as far as a PC with an ATX board is concerned, you can install any cooling system, including air, water, or even a hybrid system.

Final Thoughts

Choosing the correct motherboard for your PC can indeed be difficult, significantly, today when the technologies are changing rapidly. However, by going through this guide, you will get a fair idea about the motherboard type you need. Remember that the motherboard you need to use depends on the PC you are building and what you intend to use it.

So, when looking at motherboards, ensure that you pay attention to the number of expansion slots and other such connection ports and the different sizes. Be sure to know about the different sizes that motherboards come in, including ATX, Mini-, Nano-, and Pico-ITX, Micro-ATX, E-ATX, and XL ATX.

Martha Davis

Martha Davis is a computer hardware specialist who works extensively in designing and manufacturing hardware devices, researching advanced computer technology. She built as a platform to share her insight on computers and PC assembly with the web. Currently, she is carrying out her research on Robotics and Computer Vision and working privately to deliver services. Martha makes sure that readers of master the basics of setting up computer components like motherboard, CPUs, and GPUs through the informative articles that she writes.