Motherboard Form Factors – CompTIA A+ 220-1001 – 3.5


There are many different motherboard form factors that provide the best starting point for any project. In this video, you’ll learn about the differences between the ATX, Micro-ATX, and Mini-ITX form factors.

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The motherboard is the foundation of many computing devices. And in this video, we’ll look at a number of different motherboard form factors. One of the most obvious characteristics of a motherboard is the physical form factor, the size of the motherboard itself. We’re usually selecting a motherboard and then trying to find a case that will fit the particular motherboard form factor that we’ve selected.

The motherboard that you choose will have a basic layout. And it’s very difficult to add or subtract from that layout once you’ve selected a motherboard. For example, a motherboard may provide a certain number of expansion slots or a certain number of memory slots. It’s very difficult to add or subtract from that number once you’ve locked into a particular motherboard model.

Regardless of which form factor of motherboard you choose, the type of connectors on the motherboard will be standard across all of those different models. For example, the power connector on a motherboard will be the same on an ATX a microATX or a Mini-ITX motherboard. And with some motherboards, deciding on the size of the motherboard will also impact how much airflow you’re able to get through a particular computer case. So deciding on how you’re going to cool this motherboard may also determine whether you want to get a small motherboard or larger motherboard.

If you looked on Wikipedia, you would see there were over 40 different form factors of motherboards. Fortunately for the CompTIA A+ Exam, you don’t need to know all 40 of these. If you reference the CompTIA exam objectives, you’ll understand exactly which motherboards you need to know.

This area of the exam objectives is section 3.5 on the 220-1001 exam objectives. And they state that, “Given a scenario, you need to understand how to install and configure motherboards, CPUs, an add-on cards.” This means that CompTIA wants you to understand, what type of motherboard would be the best choice for a particular scenario?

There are, of course, many specifications and dimensions associated with these different motherboard types. But my recommendation to you is to stick to exactly what’s listed in those exam objectives. And if we refer to that list, we’ll see there are only three specific motherboard types that are listed, the ATX, the microATX, the entire ITX family– but more specifically, the Mini-ITX motherboard.

So as we go through this video, don’t worry so much about the exact dimensions of a particular motherboard type. But instead, consider whether the motherboard might be a good choice for a media center device, a video-editing device, a thin client, and the other types of systems you would find in the CompTIA Exam Objectives. Here are the three specific motherboard types that are listed in the CompTIA Exam Objectives. There’s the standard ATX motherboard, the smaller microATX, and the even smaller Mini-ITX motherboard.

The largest of these three motherboard form factors is the ATX or the Advanced Technology Extended motherboard. This was standardized by Intel in 1995. And it’s seen a number of different changes through the years.

For example, the original ATX motherboard supported a 20-pin interface for motherboard power. Newer ATX motherboards will have a 24-pin connector and then an additional four- or eight-pin connector for CPU power. This ATX motherboard continues to be popular. And you can find, ATX motherboards continue to be manufactured today.

Here’s a closer look at this ATX motherboard. As you can see, the power is here. We’ve got four memory slots. Notice, there are 1, 2, 3, 4, 5, 6 separate expansion slots available on this motherboard. That’s one of the advantages of having this larger form factor– is that you’re able to fit more components on the single motherboard.

If you’re installing a server, you might need the expansion that’s available on a full-size ATX motherboard. But a computer that’s running on your desktop might not need that much expansion. And you may not want a larger system to take up space on your desk.

For those scenarios, you might want a little bit smaller than an ATX motherboard or a microATX. You’ll sometimes see this abbreviated with the micro symbol and ATX or with the U and ATX. You can see, the size is different, especially in the number of expansion slots that you can fit onto this motherboard. This motherboard supports 1, 2, 3, 4 different expansion slots, which is different than the larger number we saw on the full-size ATX motherboard.

There are also similarities between the full-size ATX and this microATX motherboard. For example, the power supply connector on this microATX motherboard is exactly the connector you would find on an ATX motherboard. The microATX mounting points, which you can see connect this motherboard to the case, are exactly the same dimensions as those you would find on an ATX motherboard. That means you can buy a single computer case and use that same case for either ATX or microATX.

As with the ATX motherboard, microATX is also very popular. And you’ll find motherboards are actively being manufactured today for the microATX form factor. Here’s a closer look at the microATX motherboard.

You can see, everything’s a little bit closer together. We have limited amount of space. But if all you need is a CPU, some memory, and maybe one or two expansion slots, the microATX motherboard might be a perfect fit for your computer case.

There’s been a push through the years to make smaller and smaller motherboards that use less power and take up less room. One series of motherboards that provide this are the ITX form factor motherboards. This style was created by VIA Technologies in 2001. The Mini-ITX motherboard you see here is screw compatible with the ATX and the microATX motherboard, which means you can install this motherboard into exactly the same computer cases as the ATX and the microATX.

Usually, though, you’re using a much smaller computer case that takes up a lot less room. You can put it on a shelf, or put it somewhere out of the way. The smaller form factor is really designed to be a single-purpose computing device.

This might be good for a streaming media device, where you can have a very small box that sits on your TV or near your television and is able to provide streaming video without taking up a lot of space that a traditional computer might use. If we look closely at this picture, we can see just how small this Mini-ITX motherboard is. There’s our power connector here at the top.

We really only have room for two memory module slots. And you can see, these are the same memory module sizes that we saw on the ATX and the microATX. Although, in this picture, they look very large, because the motherboard is so small.

And as you can see here, we only have room for one, single expansion slot. Everything else is designed to be on the motherboard itself. So it uses as little space as possible.