PC motherboard types: ATX, Mini-ITX, Micro-ATX and E-ATX

PC motherboard types

The motherboard is the piece of hardware where the different components of the computer are connected, such as the CPU, RAM, storage units, graphics card, and so on. But there are different sizes and shapes of these and that is why, so that you can learn to identify them, we review each type of motherboard that you can find on a desktop PC.

One of the advantages that the PC has is the level of customization of its hardware and this not only includes being able to choose what type of processor, GPU, the type of SSD or hard disk , but also the type of motherboard and that is to begin with. Depending on the type of PC case that we use, we will be limited to some types of motherboard or others.

Types of PC motherboard

Tipo de Placa Base

In the PC world, when we look at the specifications of a motherboard, acronyms such as ATX, Micro-ATX-Mini-ITX , etc. appear. Well, these indicate the type of motherboard that it is and therefore the common characteristics that they have with their similar ones. Of course, we can find proprietary formats or that our computer uses a type of motherboard that does not respect the standard, especially if we have bought a PC already built.

In the event that we build a PC ourselves, the types of motherboard that we describe in this article are the ones that you will find most often, since most towers and different PC cases are designed for them. So in the event that you want to update your computer without changing the case, you will have to make sure that the new motherboard is compatible and therefore can be mounted.

That said, let’s go to the different variants one by one and see how they differ.

ATX type motherboard

ASRock Z690 Taichi

It is the most classic type of motherboard, its acronym comes from the fact that the PCs with the Intel 286 received the nickname of AT, when in 1995 the real boom of the clones or compatible PCs arrived thanks to the name of Windows 95 motherboards came to be called ATX, where X is the dimension of Enhanced or improved in English, since then they have become the standard par excellence and the most used type of motherboard.

The dimensions of this motherboard format are 305 x 244 mm , although these may vary slightly. The name ATX is also given to the power supplies that accompany this type of motherboard. What’s more, all types of motherboards derived from ATX are designed to work with their type of PSU, in addition to respecting details with the seven bays for expansion with a differentiation of 20 mm between them.

The ATX standard, being the most widely used, is in constant revision, but not in terms of its sizes, but to integrate changes in the form of new expansion and power ports, as well as the discarding of those that have become outdated. At the end of the day it is important that the different pieces can be placed in a logical and coherent way, but at the same time the different components do not disturb each other.

Micro ATX, the small form factor

Placa Base Tipo Micro ATX

The first variant of the ATX format was the so-called Micro ATX and as you may have guessed from its name it is a more compact version of the type of motherboard that we discussed in the previous section. The dimensions of its motherboards are 244 x 244 mm and this changes the position of the expansion bays of the case with respect to the motherboard.

In such a way that the four upper holes usually coincide with those of the ATX motherboard, and therefore have a space of 20 mm between them, but in the lower two the space is narrower. This is not a problem, since the vast majority of PC users do not get to use the full expandability of an ATX. Especially the low-end desktop computers used in offices and schools where they are not usually expanded. Today they are the most widely used type of motherboard for mounting PC Gaming, mainly due to the fact that they offer the level of configuration and expansion that is needed.

Mini-ITX, for compact PCs


Regarding the creation of small desktop PCs, we have the so-called Mini-ITX motherboards, which are not a derivative of ATX, since this type was created in 2001 by VIA Technologies. It is a 170 x 170 mm motherboard and its small size usually means that they bring fewer components than the types of motherboard that we have discussed before, but the integration of components has made that over time they are as good in that aspect as ATX and derivatives.

It is its small size that causes certain problems when assembling certain components, especially cooling systems such as radiators and heat sinks, which are designed for ATX and Micro-ATX type systems. We can also find graphics cards of a more compact size and therefore narrower in length, which are designed for Mini-ITX boxes.

Although we can find towers that support a Mini-ITX plate, since its four holes usually coincide with the four located on the left and central part used by plates in ATX format, its use in a box for ATX or Micro-ATX it’s a waste of your space. Therefore, they are recommended for the creation of HTPC or other compact systems where space is a luxury and it is necessary to make the most of it and where only smaller power supplies can be installed.

E-ATX, for high-end

Z690 Glacial Extreme

The last type that we are going to discuss goes to the extreme, since we have gone from largest to smallest, but when we talk about the E-ATX type we are dealing with motherboards that are not intended to be used in ordinary PCs, since they are used in both workstations and small servers.

As you may have deduced, its size is even larger than the ATX, and is that the E in its name means Extended and in effect the size of this type of motherboard is 305 x 330 mm , which allows it to have a greater number of components such as more than one CPU socket inside, more DIMMs to have more memory channels, and so on.

It is not a commonly used format and this leads to many PC cases having problems when mounting them, so if you are interested in mounting a workstation or a server at home you should take a good look at the specifications of the tower you are going to use. to know if you are going to be able to use this type of motherboard.