Motherboard Form Factors and Popular Sizes Explained


Understanding motherboard form factors can be confusing, but don’t worry – we’re here to help!

When building a PC, selecting the correct form factor for your motherboard is essential as it serves as the foundation that links all other components of your computer.

What is Motherboard Form Factor?

Motherboards come in different form factors that can fit inside various computer cases. The form factor determines the size, shape, and capabilities of the motherboard. Common form factors include ATX, Micro-ATX, Mini ITX and more recently Extended ATX (EATX). Each of these has different dimensions and power requirements depending on what type of processor it will accommodate. Additionally, they also have varying slots for RAM and expansion cards.

The right form factor should be chosen based on your intended use case for your PC build. Ensuring compatibility between components like GPUs or CPUs with the chassis form factor is also important when selecting a motherboard as some may not fit into certain cases due to their size or design limitations. With this in mind, you should take into account all possible scenarios when choosing the best motherboard form factor for your build so that all parts can work together smoothly.

Knowing the right motherboard form factor for your build is essential for compatibility and efficient performance. The form factor, also known as a board size or layout, determines which components can be used in the computer system. It affects the number of expansion slots, types of memory modules, and other features you may want to use.

Below are a few considerations when selecting a motherboard form factor:

  1. Size: Consider how much space you have available in your PC case and if it can accommodate larger motherboards such as ATX or Micro-ATX sizes that have more component options than smaller boards like Mini-ITX sizes.
  2. Power delivery: You should check the power requirements of each component to make sure that it will be compatible with the power delivery from the chosen form factor’s power supply unit (PSU).
  3. Features: Pay attention to any additional features such as built-in Wi-Fi or Bluetooth connectivity, audio ports, USB ports, and other connectors that could be beneficial depending on what type of applications you plan on using.

Having an understanding of different motherboard form factors will help you select one that fits your specific needs while avoiding potential compatibility problems down the line.

From there, we can move on to discussing ‘types of motherboard form factors’ in more detail.

Types of Motherboard Form Factors


ATX, with dimensions of 12” x 9.6” or 305mm x 244mm, is the prevalent form factor. It provides generous expansion possibilities, usually encompassing six PCIe and four RAM slots. Suitable for various builds, ranging from mid-tier gaming computers to top-tier workstations, ATX motherboards are a favored choice. Their compatibility with an extensive array of cases adds to their appeal, making them an outstanding option for those seeking greater flexibility in their construction.


  • The advantages of motherboard form factors include their ability to provide plenty of room for expansion, a standardized layout for easy compatibility with other components, and the availability of a wide range of motherboards.
  • With multiple expansion slots, a large number of memory slots, and an array of compatible components available on the market, motherboard form factors make it easy to customize your system in whatever way you desire.

However, some potential drawbacks must be taken into account when choosing the right form factor.


While there are advantages to using large form factor motherboards, there are also some distinct disadvantages. These include:

  • Size: Large size makes it hard to fit in small form factor builds.
  • Case: Requires a more significant case to accommodate the motherboard.
  • Power consumption: Higher power consumption due to the larger size and number of components.

Overall, these factors can make a large form factor motherboard less than ideal in certain situations.

We’ll look at how micro ATX motherboards compare.

Micro ATX

MicroATX is an attractive form factor for those looking for more expansion options than Mini ITX. Its smaller size of 9.6” x 9.6” or 244mm x 244mm allows it to fit into most ATX cases, making it a great choice for gaming PCs or small workstations.

However, the MicroATX does have some disadvantages such as having fewer RAM and PCIe slots than ATX boards. But this can be offset by the cost savings when compared to larger form factors.


MicroATX motherboards have several advantages for those seeking a more compact form factor and lower power consumption.

  • The smaller size and fewer components make them ideal for smaller builds.
  • Additionally, they consume less power, which can be beneficial for energy efficiency.
  • Another advantage is that MicroATX motherboards can fit in ATX cases, allowing users to utilize high-end cooling systems.
  • Overall, MicroATX motherboards offer a good balance between performance and efficiency. However, it is important to consider potential drawbacks before making a selection.


Despite the advantages, there are some potential drawbacks to choosing a MicroATX motherboard.

  • Expansion slots and memory slots are much fewer than with an ATX form factor, thus limiting upgradability and maximum memory capacity.
  • Additionally, many manufacturers produce fewer MicroATX motherboards due to their smaller size and lack of demand, making them harder to find.
  • Ultimately, these factors must be weighed when deciding if a MicroATX is the best choice for your system.

We have compared Micro-ATX and ATX in detail.

Transitioning now into the next form factor: micro mini-ITX.

Micro Mini-ITX

I’ve noticed that Mini-ITX motherboards are gaining popularity these days simply because of how compact they are.


  • You benefit from the Mini-ITX form factor’s smaller size and fewer components, which leads to lower power consumption.
  • Its portability is a bonus, making it easy to move around or even travel with. It also has a similar layout to the ATX and Micro-ATX form factors for compatibility with other components.
  • Benefiting from these advantages, you can build a powerful system in a compact space without worrying about power requirements or compatibility issues.

However, some potential disadvantages should be considered before investing in this form factor.


The advantages of the micro-ATX form factor may seem attractive, but there are also some significant disadvantages.

  • As mentioned previously, limited expansion slots can limit upgrades, while limited memory slots can restrict how much RAM can be installed.
  • Furthermore, it cannot accommodate many of the larger graphics cards and is less widely available than ATX form factors due to its smaller size.
  • However, if you’re looking for a compact solution with fewer bells and whistles, then the micro-ATX may be worth considering.

Next, we’ll look at other form factors such as mini-ITX and nano-ITX.

Micro Nano-ITX

Introduced in 2003 by VIA Technologies, Nano ITX is the pioneer among the smaller ITX boards. With dimensions of 12cm x 12cm (4.7 inches), Nano ITX motherboards are fully integrated and characterized by their minimal power consumption. Due to their compact size, many of these motherboards find direct application in smart entertainment systems and in-vehicle devices.

Advantages of Nano-ITX Motherboards

  • Nano-ITX motherboards are highly advantageous due to their incredibly small size, making them perfect for compact builds. Their small form factor allows for more flexibility in terms of placement and space limitations.
  • They also offer higher power efficiency compared to larger motherboards, reducing thermal output and allowing users to increase the longevity of their hardware. Furthermore, due to the smaller components used in Nano-ITX boards, they are typically more affordable than other form factors.

However, there are some downsides which will be discussed next.

Disadvantages of Nano-ITX Motherboards

Having discussed the advantages of Nano-ITX motherboards, it is important to also consider their drawbacks. The major disadvantages are summarized in the table below:

Disadvantage Explanation
Limited upgradability Due to their size, Nano-ITX motherboards do not offer much room for expansion.
Expense These boards cost more than larger form factors. 
Lack of compatibility Not all components work with this form factor.
Poor cooling capabilities Heat sinks and fans cannot be easily added or replaced.

Overall, Nano-ITX motherboards can provide a great deal of computing power in a tiny package, but they come at a price and have some limitations that should be taken into consideration before investing in them. With that being said, let’s take a look at another type of motherboard form factor: micro Pico-ITX.

Micro Pico-ITX

Pico ITX, another creation by VIA Technologies, is the tiniest in the ITX board series, measuring just 3.9in x 2.8in, which is half the area of Nano ITX. This minuscule size was developed to pave the way for further innovation in the smallest and most intelligent IoT devices. Achieving this level of compactness while delivering performance with a low TDP has unlocked new possibilities for services that were once unattainable

Advantages of Pico-ITX Motherboards

You’ll benefit from the small size of Pico-ITX motherboards, as they are the smallest form factor available.

Their advantages include:

  • Reliability – their miniaturized design ensures fewer components and less complexity.
  • Efficiency – these boards offer improved performance in a smaller package.
  • Versatility – they can be used in embedded systems or scaled for larger applications.

Plus, they are low power, cost-effective solutions for various computing needs. This makes them an ideal choice for those seeking a powerful yet compact option.

Despite these benefits, there are drawbacks to consider before investing in one – let’s explore this further…

Disadvantages of Pico-ITX Motherboards

Although they offer many advantages, you should be aware of the potential drawbacks that come with Pico-ITX boards before investing in one.

The small size and low cost of Pico-ITX motherboards can be both a blessing and a curse. As such, it’s important to weigh these pros and cons carefully before deciding if this form factor is right for your needs. Now let’s discuss the e-ATX form factor.


E-ATX stands as the most substantial form factor, with dimensions of 12” x 13” or 305mm x 330mm, or even larger. As the largest form factor, it furnishes an abundance of expansion possibilities, typically providing up to eight PCIe slots and eight RAM slots. E-ATX motherboards are apt for high-end constructions, including gaming setups or workstations that demand significant processing power.


Gaining multiple expansion slots, a large number of memory slots, improved heat dissipation, and the ability to add multiple GPUs are just some of the advantages of larger motherboard form factors.

The main benefits include:

  • Improved Performance:
  • Increased speed due to more efficient hardware layout.
  • More RAM and storage capacity for running complex programs.
  • Flexibility:
  • Ability to upgrade with additional components without needing a new board.

These advantages allow users to build powerful and flexible systems that can tackle any computing task. Moreover, transitioning into the next section about disadvantages will further illustrate these points.


While the larger size of the extended ATX form factor provides advantages, there are some notable drawbacks. Power consumption is high due to its expansive components and size, while availability of motherboards is limited by its lower demand. Moreover, it requires a larger case to fit this motherboard type, making it an impractical choice for small form factor builds.

Despite these disadvantages, the extended ATX form factor remains a viable choice for those who want more control and options from their PCs.

Moving on, let’s take a look at femto-ITX next.


FEMTO-ITX motherboards have become increasingly popular due to their small form factor and ability to provide versatile I/O in industrial applications. Despite their size, FEMTO-ITX motherboards offer users the advantage of having more connectors and ports than larger form factors like E-ATX.

However, one of the biggest drawbacks of using a FEMTO-ITX is that they are not as powerful as other motherboards. This is because they are designed with space efficiency in mind.

Advantages of FEMTO-ITX Motherboards

You’ll benefit from the small size of FEMTO-ITX motherboards, as they can fit into a variety of compact spaces. This makes them ideal for tight builds in small form factor cases and devices such as embedded systems or kiosks.

They also provide improved thermals due to their increased surface area to dissipate heat generated by the components. And, with fewer expansion slots than larger form factors, you’re able to reduce the overall cost without compromising your desired performance.

Despite these advantages, FEMTO-ITX motherboards still have some drawbacks that must be considered when making your purchase decision.

Disadvantages of FEMTO-ITX Motherboards

Despite the advantages, there are some downsides to using FEMTO-ITX motherboards that you should be aware of before deciding:

  • Limited expansion capabilities due to its small size
  • More expensive than other form factors
  • Difficult to find compatible components

Therefore, before choosing a motherboard for your system build, be sure to consider all the pros and cons of each form factor.

Moving on, what do mini-ITX, microATX, and ATX motherboards have in common?

What Are Industrial Motherboards And How Are They Different

Industrial motherboards are designed differently than commercial ones, offering a small form factor and low power consumption for industrial applications. Advantages of these boards include:

  • Size: Smaller size enables the placement of complete systems in limited space.
  • Power efficiency: Low processing power helps to reduce cooling costs while prolonging the life span of the system.
  • Longevity: Parts are selected specifically to deliver a long life without maintenance or replacement needs.
  • Durability: Built to withstand harsh deployments with dust, debris, water, shock, and vibration.

The simple design eliminates unnecessary add-ons while providing features that match various types of deployments. This makes industrial motherboards an ideal solution for entry-level industrial workloads that require just enough power consumption and performance.

As such, they offer an efficient way to perform computing solutions in difficult settings. Transitioning easily into the next section on ‘brief comparison of motherboard form factors’, it is clear how different these boards can be for different situations.

Brief Comparison of the Motherboard Form Factors.

Understanding the differences between various board sizes and features can help you choose the right one for your project. Below is a comparison of some of the most common motherboard form factors:

Form Factor Size Features
ATX 305mm x 244mm Standard size with many expansion slots
Mini ITX 170mm x 170mm Compact size with fewer expansion slots
Micro ATX 244mm x 244mm Smaller than ATX with fewer expansion slots
Nano ITX verych form factor has its advantages and disadvantages, depending on what type of hardware or software you need. For instance, if you require more memory or slower storage options, an ATX form factor would likely be your best choice due to its larger size which provides more space for extra components. On the other hand, if you need something that will fit in a tight space like a home theatre PC case, then a Nano ITX might be more suitable as it is so small it can easily fit inside these cases without taking up too much room. By understanding the different types of motherboards available on the market today and their capabilities, you can make an educated decision about which will suit your needs most effectively.  

Form Factors and Some of Their Applications

Choosing the right form factor for your project can make a huge difference in its performance.

Two of the most popular motherboard form factors are Mini-ITX and IoT solutions, each having different applications:

  • Mini-ITX:
  • Perfect for vehicle computers due to their powerful performance yet reduced format, allowing them to be installed in limited spaces.
  • Comes with built-in GPS, multiple antennae I/Os, 2x serial COM ports, 2x video outputs (DVI-D), USB and Digital I/O ports, and storage options up to SATA/mSATA.
  • IoT Solutions:
  • Smart LED street illumination that enables sensors, wireless communication points, and open interface technologies.
  • Compact design with fanless thermal mechanism able to resist a wide range of operating temperatures (-40°C – 70°C).
  • Intel® Atom™ E3815 processor and DDR3L at 1.333 MHz SO-DIMM memory up to 4GB plus abundant I/O connectors like VGA display, USB ports, etc.

Having all this information in mind will help you choose the right form factor, which is essential for your project’s success.

Importance of Choosing The Right Form Factor

Selecting the correct form factor is critical, as it directly impacts the size and shape of your PC build. This determines which case your motherboard can fit into, as well as the number and type of expansion slots available. Moreover, it ensures compatibility with other components and provides the necessary features for a successful system.

To get the most from any PC build, choosing the right form factor is essential.

It’s important to consider what type of processor you have when selecting a motherboard form factor as some processors are only compatible with certain sizes or types of boards. Additionally, factors like how much RAM and storage space you need should be taken into account since this will help determine which form factor best suits your requirements. Furthermore, if you plan on adding extra graphics cards or other components in future expansions then make sure to choose a form factor that supports them too.

Overall, choosing the correct motherboard form factor is an integral part of any successful PC build. It not only affects compatibility but also has an impact on performance and reliability over time so getting it right is essential for achieving optimal results. By understanding all the considerations that go into selecting a board form factor, you can confidently ensure you’re making the right choice for your setup and maximize its potential in terms of power and efficiency.

From here we can conclude…


In conclusion, the right form factor is essential when designing a motherboard. It can determine the size of the device, its casing, power supply, and overall layout. The most common form factors are ATX and ITX. ATX has evolved to mini-ATX, nano-ATX, pico-ATX, and more. ITX is smaller than ATX and also comes as nano-ITX, pico-ITX, mobile-ITX, and others.

Choosing the right form factor helps ensure your design meets all requirements for performance and compatibility with different hardware components. Understanding these differences is critical for successful product development processes.

Frequently Asked Questions

What are the advantages and disadvantages of each motherboard form factor?

When considering a motherboard form factor, it’s important to weigh the advantages and disadvantages of each.

ATX is the most popular and reliable form factor due to its size, design, and compatibility with a wide range of components.

A downside is that it can be difficult to fit inside smaller cases.

Micro-ATX offers more flexibility in terms of case compatibility but may not provide as many expansion slot options.

Mini-ITX is the smallest option and provides less space for components, making it difficult to upgrade or expand in the future.

Its advantage is that it takes up minimal space inside a PC case.

Ultimately, choosing a motherboard form factor comes down to personal preference and understanding what type best fits your needs.

What is the most popular motherboard form factor for gaming?

Playing the game of building a gaming computer is like navigating a maze. One of the most important decisions you can make is choosing the motherboard form factor. ATX form factor motherboards are by far the most popular choice for gaming. They offer flexibility and superior features. ATX motherboards provide more space for components, multiple PCIe slots, expansive RAM capacity, and advanced cooling capabilities. However, the downside is that they take up significantly more room compared to other form factors. Ultimately, if you’re looking for the best performance with maximum upgradability potential, ATX is your go-to choice.

How do the cost differences between the different form factors compare?

The cost differences between the different motherboard form factors can vary greatly. ATX motherboards tend to be more expensive than smaller form factor boards, while Micro-ATX and Mini-ITX boards are much cheaper.

The cost also depends on the features each board offers — a gaming motherboard with advanced features will be more expensive than one without them.

Generally, when it comes to getting the most bang for your buck, Mini-ITX boards offer the best performance for their price range compared to larger form factors.

What other components are compatible with each form factor?

As an enthusiast, I’m aware that compatibility of components is a major factor in building a custom PC. With the right form factor, you can choose from many different components to create the perfect machine.

For example, when it comes to ATX motherboards, which are often used for gaming rigs and workstations, they are compatible with an array of CPUs from AMD and Intel as well as RAM modules in various sizes and capacities.

Similarly, Mini-ITX motherboards have the advantage of being smaller than their ATX counterparts yet still support multiple CPUs and RAM modules.

Ultimately, understanding the different form factors available will help you select the best combination of components for your build.

Are there any form factors that are better for overclocking?

Yes, certain form factors are better suited for overclocking. Generally speaking, larger form factors like E-ATX and ATX offer more space for additional components such as cooling solutions that may be beneficial when trying to overclock.

Additionally, these large form factors often have more power connectors and ports which can provide more stable power while overclocking.

On the other hand, smaller form factors such as Mini ITX typically don’t have enough room to house extra components needed which can limit the maximum achievable clock speed.

I am a computer engineer holding a bachelor's degree in Computer Science, complemented by a Master's in Business Administration from University of Strathclyde, Scotland. I currently work as a Senior IT Consultant in Melbourne, Australia. With over 15 years of...