Building a new gaming rig or work computer? Learning about ATX vs Mini-ITX vs MicroATX motherboards is an excellent starting point. That’s because the motherboard is the foundation of your computer, and each type is best suited for different purposes. If you get this part wrong, it can really mess with the rest of your setup.

Fortunately, choosing the right motherboard isn’t rocket science. We’ve put together this convenient guide to demonstrate the major differences between the three most popular starting points. We’ll also look at the best purpose for each option and how to pick the right one for your rig. Let’s jump right in.

ATX vs Mini-ITX vs MicroATX Motherboards

A motherboard is the foundation of your computer. It takes the form of a printed circuit board, or PCB, that connects all of a computer’s components. This includes critical hardware like the RAM and hard drive, as well as expansion slots for upgrades like graphics cards and other peripherals.

ATX, Mini-ITX, and MicroATX motherboards are the most common types of motherboard, and they all work great for office and gaming PC builds alike. That’s because they’re all equipped with everything you need for today’s most common computing tasks. Still, some are better than others for certain tasks and choosing the right one is crucial for nailing down your dream build.

Motherboard Example

To make comparing them as simple as possible, let’s look at how they stack up in the following 5 categories. We’ll start with size & design.

Size & Design

What size are ATX vs Mini-ITX vs MicroATX motherboards? Well, the specifications of each form factor are as follows:

ATX: 12″ length x 9.6″ width
MicroATX: 9.6″ length x 9.6″ width
Mini-ITX: 6.7″ length x 6.7″ width

For a better visual representation of this size differential, you can see how they measure up in the image below.

Motherboard Sizes Illustration

MicroATX vs Mini-ITX vs ATX Size Comparison

Regardless of size, each motherboard has its own unique design that is independent from its form factor. This is particularly important to consider if you plan to use an open-display case or add enhancements like LEDs. For the most part, ATX motherboards are the best for aesthetics, as they feature the most room for upgrades.

Still, that’s all surface level stuff. Size and design really become important when you start to think about components like RAM.

RAM

RAM, or random access memory, is critical hardware that affects the overall speed of your machine. ATX and MicroATX motherboards are both equipped to handle 4 sticks of RAM. Plenty for even the highest-end gaming PCs.

RAM

Mini-ITX motherboards, on the other hand, only have enough room to handle 2 sticks of RAM. While the difference between the 2 and 4 RAM modules shouldn’t be an issue for most users, it can affect those seeking maximum performance.

Ram Capacity:

  • ATX & MicroATX – 4 RAM Modules
  • Mini-ITX – 2 RAM Modules

Another huge consideration that differs between ATX vs Mini-ITX vs microATX motherboards? PCIe slots.

PCI Express Slots

In terms of expansion potential and upgradability, all motherboards are not created equal.

PCIe, aka Peripheral Component Interconnect Express, is an expansion slot that allows you to customize and add more, well, peripheral components. These peripherals include things like graphics cards, additional drives, and other cool upgrades.

PCIe Expansion Card

PCIe Expansion Card

ATX, Mini-ITX, and MicroATX motherboards each come with a different number of PCIe slots. Take a look:

ATX: Up to 7 PCIe slots
MicroATX: Up to 4 PCIe slots
Mini-ITX: Up to 1 PCIe slots

If you’re fine with a simple build that uses integrated graphics, a Mini-ITX motherboard is perfect. If you want to build a single-GPU PC that can handle most games just fine, a MicroATX is your best bet.

But if you’re looking for a top-notch multi-GPU PC, you’ll definitely want to go with an ATX motherboard. And yes– the extra performance comes at a price.

Price

Which do you think is the most expensive? An ATX vs Mini-ITX vs MicroATX motherboard?

If you said MicroATX, you’re correct! That’s because MicroATX motherboards are the most common among the three, and top manufacturers are competing for your dollar.

That said, you’d be forgiven for thinking that a Mini-ITX motherboard was the cheapest. But despite its small size, it’s more of a specialty component that involves lots of complex circuitry. And, there just isn’t the same demand as with MicroATX motherboards.

ATX motherboards lie somewhere in the middle. You can still pick up a nice ATX board for fairly inexpensive, despite the fact they they use the most materials. Do note, however, that the cost of an ATX build quickly outpaces the others when you factor in all your other parts.

At the end of the day, price is determined by quality. These are estimates, not exact breakdowns of cost. And every motherboard is unique.

One thing that’s certain? The more you spend, the more performance you’re likely to see.

Ram Slots

Performance

So, what’s the verdict in terms of Mini-ITX vs mATX vs ATX motherboard performance? We’ve compared the three models to give you a detailed look at how each one stacks up against the others.

ATX vs Mini-ITX Motherboard Performance

By and large, you’re going to see more performance from an ATX motherboard than from a Mini-ITX motherboard. That’s because ATX motherboards are almost twice as big as Mini-ITX motherboards and they’re designed to power high-end rigs.

However– in terms of portability, Mini-ITX motherboards outshine their ATX counterparts all day long.

ATX vs MicroATX Motherboard Performance

Comparing MicroATX vs ATX motherboard performance?

ATX motherboards are designed to power the most robust PCs around. That said, builders rarely make use of the full potential that ATX motherboards offers. And in many cases, a MicroATX motherboard is simply a better fit for your build. This is especially true when you compare ATX vs mATX size profiles.

But– in terms of pure performance potential, ATX motherboards take the cake.

Mini-ITX vs MicroATX Motherboard Performance

Both are designed to be small and easy to work with. Both have fewer PCIe slots than ATX motherboards. And both can be used for many of the same purposes.

That said, a Mini-ITX motherboard simply isn’t equipped to handle today’s most intensive games. While they’re fine for lighter titles and everyday computing, you’ll need a MicroATX motherboard to handle the rest.

Case Comparison

ATX vs Mini-ITX vs MicroATX Case Size Comparison

Pros and Cons of Each Form Factor

Next let’s look at the top pros and cons of each motherboard to get an idea of how and when each one should be used.

ATX Motherboards

 Standard ATX Motherboard

The largest of the three, ATX motherboards feature several advantages over their smaller counterparts.

PROS:

  • Plenty of PCIe slots
  • Great for multi-GPU setups
  • Can handle the most intensive tasks and games

CONS:

  • Largest form factor
  • Fairly expensive

Verdict: ATX motherboards are ideal for high-end builds that prioritize power and maximum performance.

Mini-ITX Motherboards

Mini ITX Motherboard

The smallest of the three, let’s see how Mini-ITX motherboards measure up.

PROS:

  • Compact design
  • Portable
  • Great for LAN parties

CONS:

  • Limited to 2 RAM modules and 1 PCIe component
  • The most expensive option

Verdict: Mini-ITX motherboards are perfect for portability and in spaces that require a small footprint.

MicroATX Motherboards

Micro ATX Motherboard

If you’re looking for a happy medium, MicroATX motherboards may be the answer.

PROS:

  • Highly balanced
  • Popular for gaming
  • Most affordable

CONS:

  • Only 4 PCIe slots
  • Not quite stationary, but not quite portable either

Verdict: MicroATX motherboards are the best suited for gaming due to their convenient size, expandability, and price.

Motherboard Close Up

Frequently Asked Questions

We’ve curated this FAQ to answer the most common questions about ATX, Mini-ITX and MicroATX motherboards. If you have a question that you don’t see on this list, please don’t hesitate to contact us. We’d love to get your question answered too.

What is the smallest PC motherboard?

When considering the physical size of ATX vs Mini-ITX vs MicroATX Motherboards, Mini-ITX motherboards are the smallest.

What is Mini-ITX used for?

Mini-ITX motherboards are typically chosen for their small form factor and convenience. They’re great for small spaces and portability.

Is Mini-ITX good for gaming?

That depends on the particular setup. Generally speaking, Mini-ITX motherboards aren’t as powerful as mATX or ATX motherboards. That said, Mini-ITX motherboards can still pack quite the punch, and they’re great for LAN parties.

Which operating systems can be installed on Mini-ITX motherboards?

Microsoft Windows and Linux operating systems can be installed on Mini-ITX motherboards.

Is Mini-ITX expensive?

Even though Mini-ITX motherboards are smaller than their counterparts, they’re more of a specialty item. As such, you’ll likely pay a premium for Mini-ITX motherboards and Mini-ITX cases.

Is MicroATX the same as Mini-ITX?

No, they are completely different form factors that use different technologies.

Is Mini-ITX or MicroATX bigger?

Is MicroATX bigger than Mini-ITX? Yes– in terms of MicroATX vs Mini-ITX size, MicroATX motherboards are several inches bigger than their Mini-ITX counterparts.

What is uATX?

uATX is just another way to say MicroATX.

What Does ATX and ITX stand for?
How can you tell the difference between ATX, MicroATX and Mini-ITX?

The easiest way to tell the difference is by looking at the size of the motherboard in question.
ATX motherboards are 12″ x 9.6″, MicroATX motherboards are 9.6” x 9.6”, and Mini-ITX motherboards are 6.7” x 6.7”.

Further Reading

Enjoy our guide on today’s most popular motherboards? If you’re still seeking advice on which one is right for you, check out our in-depth buying guides below: