Micro ATX vs ATX: A Detailed Comparison


Micro ATX (M-ATX) and ATX motherboards differ in size, with ATX being larger. ATX offers more RAM and PCIe slots, allowing for greater expandability but at a higher cost and power consumption. M-ATX is more compact and affordable, making it suitable for those prioritizing space efficiency and budget over expandability options.

As a PC enthusiast, you may have considered building your computer but are unsure about the size of the motherboard that is best for your build. If yes, then this article will provide an in-depth comparison between Micro ATX and ATX form factors so you can make an informed decision when constructing your PC setup.

We’ll look at their similarities and unique characteristics regarding dimensions, power consumption, and available slots for components – all helping you identify which option will be best suited for what kind of project.

Finally, we’ll offer some general advice on deciding whether to use a microATX or ATX motherboard so you know exactly what hardware suits your needs!

What is Micro ATX?

MicroATX is a form-factor of motherboard that shares many features with an ATX motherboard but in a smaller size. This allows Mini ITX builds to fit more powerful hardware into a smaller space.

Definition and Dimensions of Micro ATX

Micro ATX is a commonly used form factor in gaming PCs. This type of motherboard is slightly smaller than ATX motherboards – having width and length measurements of 11.2″ x 8.2″ (284mm x 208mm).

As such, the number of PCIe slots available on mATX motherboards is typically fewer, as well as USB and SATA connectors compared to the full-sized version. It’s important to note that while an mATX motherboard can fit into certain cases designed for ATX motherboards, they may not maximize their space-saving benefits fully due to size constraints.

The upside to this is that Micro ATX PCs offer many component options despite their more compact and lightweight construction – weighing only a few pounds because their chassis isn’t large or excessively heavy like some other form factors.


Advantages and Disadvantages of Micro ATX Motherboards

Micro ATX, also known as mATX, offers a unique set of benefits and challenges. Understanding these characteristics will help you make a more informed decision about whether this type of motherboard is the right fit for your needs.

Advantages of Micro ATX:

  • Compact Size: Micro ATX motherboards are smaller in size compared to their ATX counterparts. This makes them an ideal choice for small form factor builds or for systems where space is at a premium.
  • Affordable: Generally, Micro ATX motherboards are more affordable. Their smaller size often translates to a lower cost, making them a budget-friendly choice for many users.
  • Sufficient for Most Users: Despite their smaller size, Micro ATX motherboards can still accommodate a decent number of components, making them sufficient for the needs of most mainstream users.

Disadvantages of Micro ATX:

  • Limited Expandability: Due to their small size, Micro ATX motherboards have fewer PCIe slots and USB and SATA connectors compared to ATX motherboards. This restricts the potential for adding additional components or upgrades in the future.
  • Cooling Potential: The compact size of Micro ATX motherboards may limit the cooling potential, particularly for high-performance components that generate a lot of heat.
  • Fewer Choices: There tend to be fewer choices in terms of cases and motherboards when choosing Micro ATX. This can limit the customization options for your build.

Balancing these advantages and disadvantages will help you decide if a Micro ATX is the appropriate choice for your specific needs and preferences.

What is ATX?

ATX has a set of defined dimensions and features, with the largest being 12in x 9.6in, offering increased connectors, PCIe slots, more RAM slots, and bigger form factors for different PC components compared to its Micro ATX counterpart.

Definition and Dimensions of ATX

ATX (Advanced Technology eXtended) is a type of motherboard form factor that was first released in 1995 and has grown to become the current industry standard. ATX refers to the size, shape, and layout of a motherboard which determines its compatibility with different case sizes and sets the maximum number of slots available for expansion cards, RAM modules, drive bays, cooling systems, or other hardware that can be installed.

The standard ATX motherboard measures 305 x 244 mm with four RAM slots allowing up to 64GB capacity in total; it also includes multiple PCIe slots enabling parallel connection between hard drives or graphic cards.


Additionally, ATX motherboards come equipped with SATA connectors supporting up to 8 devices expecting a 3Gbps transfer rate per port as well as USB ports compatible with up to 14 peripherals using 480 Mbps data transferring speed.

Thanks to this generous supply of features combined into one single board package such an overall design helps optimize space usage inside the case while increasing adaptability for more powerful components when using advanced technology standards at optimal speeds.

Advantages and Disadvantages of ATX

Despite their larger size, ATX motherboards have unique benefits and drawbacks.

Advantages Disadvantages
Greater number of PCIe slots and SATA and USB connectors allows for more components to be added. ATX motherboards are larger in size, meaning they require more space within a computer tower.
More efficient use of space allows for the addition of components such as sound cards, graphic cards or additional storage drives. They have a higher power consumption due to the larger size and additional components.
Expanded compatibility options mean that ATX motherboards can work with a wider variety of components. ATX motherboards are generally more expensive due to the advanced features they offer.
ATX motherboards have better cooling capabilities because they have more room for fans and heat sinks. Not as portable as Micro ATX due to their larger form factor, making them less suitable for small, compact builds.
Supported by a large number of manufacturers, leading to a greater choice in aesthetics, features, and performance. Upgrading a single component might require a larger investment, as ATX motherboards can be less flexible with small upgrades.

A key factor to consider before deciding on an ATX motherboard is whether the advantages outweigh the potential disadvantages for your specific needs and constraints.

Micro ATX vs ATX: Key Differences between them

These motherboards differ in terms of size, number, and type of RAM/PCIe slots, power consumption levels, and cost.

Size and Form Factor

When comparing Micro ATX and ATX motherboards, there is a significant difference in size. ATX motherboards measure 305 x 244 mm, while M-ATX motherboards measure only 244 x 244 mm.

These measurements can make all the difference when it comes to case compatibility. For example, an M-ATX motherboard won’t fit into a full-size tower case, but it will fit into most mid-size towers.

On the other hand, an ATX motherboard usually fits both full and mid-size towers with no problem. In terms of space efficiency, most cases designed for larger form factors are going to be more efficient than those designed for smaller form factors like micro or atx and micro- or mini itx boards – however, you may get by just fine if your focus is on miniaturization rather than expandability needs.

Number of RAM/PCIe Slots

When it comes to choosing the right motherboard for your system, one of the most important factors to consider is the number of RAM and PCIe slots available. ATX motherboards are typically larger than M-ATX boards and usually have two ram slots and four RAM slots, allowing for a maximum capacity of 64 GB.

On top of that, they generally support a greater number of expansion cards via their additional PCI Express Slots when compared to Micro ATX motherboards. Motherboard manufacturers list these specifications carefully on their products so be sure to double-check what’s available before purchase.

It’s worth noting that having more slots can give you better expandability options but at an increased cost due to larger boards requiring extra components and materials such as resistors, capacitors, etc.

Power Consumption

One of the major differences between Micro ATX and ATX motherboards relates to power consumption. Generally speaking, an ATX motherboard is more powerful than an M-ATX board due to its larger size and additional PCIe slots and connectors.

As such, an ATX system usually draws more power compared to one built with a M-ATX board. That said, power consumption can vary from configuration to configuration so it’s important to consider all components when making your selection.

The amount of RAM installed may have a bigger impact on your total energy draw than simply switching form factors in some cases. Similarly, high-power components like graphics cards often influence peak electricity usage regardless of whether you go with Mega or Standard-sized boards for your build setup.

motherboard-showing-form-factor Cost

When it comes to comparing the cost of Micro ATX and ATX PCs, the larger size and more advanced features found in ATX can typically make them more expensive than their M-ATX counterparts.

Since M-ATX cases are smaller and lighter due to fewer components needed, materials for production costs are reduced meaning that overall the PCs tend to be more affordable. In addition, standard motherboards with unlocked CPUs tend to be cheaper on a per PCB level when compared against ATX boards allowing for further savings on an upgrade path.

Mini ITX is even smaller than M-ATX reducing space requirements even further making them ideal for those looking to save money while sacrificing only minimal expandability options.

Related post: ATX vs EATX: What are the differences

Micro ATX vs ATX: Factors to Consider When Choosing between them

From size and form factor to several RAM/PCIe slots, power consumption to cost, consider each component carefully when making your decision. Take the time to compare all available options so you can make an informed choice for your build!

Space Limitations

When looking for the best motherboard form factor, one of the major considerations is size compatibility. Depending on your needs and space requirements, either a Micro ATX (M-ATX) or an ATX motherboard will be more suitable.

M-ATX offers space-saving benefits due to its smaller form factor which allows for a compact chassis in comparison with an ATX build. Additionally, these cases come in various designs from lightweight builds to noise-cancelling setups that allow users to show off their hardware components inside of it.

On the other hand, while there may not be much of a difference between all M-ATX models and traditional ATX motherboards from a component options standpoint – you are likely better off sticking with larger motherboards with full-sized cases as they provide greater expandability options if such need ever arose down the line.

Expandability Needs

When choosing between a Micro ATX (M-ATX) and an Advanced Technology Extended (ATX) motherboard, expandability needs are one of the most important factors to consider. While M-ATX motherboards have fewer PCIe slots, and USB and SATA connectors, and may have fewer M.2 drive mounts than an ATX motherboard, they still boast enough support for most basic PC builds.

On the other hand, ATX motherboards typically include more PCIe slots and SATA/USB connectors which could enable superior component compatibility options down the line. However, when using an ATX form factor in tight quarters amplification might be limited due to size constraints so it’s important to make sure you know what kind of rebuilds or upgrades you’ll need in your final build before looking into a new board as well as plan ahead with plenty of room for expansion.

In addition to plentiful connection points on each motherboard form factor, motherboard manufacturers also often provide better levels of components depending on their type such as increased cooling capabilities with larger radiators that can fit onto either Motherboard Form Factor.

Power and Performance Requirements

When choosing between a Micro ATX board and an ATX motherboard, an important factor to consider is power and performance requirements. Generally speaking, the larger size and form factor of an ATX motherboard allows for more PCI Express slots which can provide better system processing capabilities and allow for more expandability options.

In addition, the larger board typically supports up to 8 DIMM slots allowing for greater RAM space allocations. The increased PCIe ports also mean that there will be more SATA connectors available providing additional expansion options in terms of storage drives such as both HDDs and SSDs.

On the other hand, smaller M-ATX motherboards usually come with fewer components due to their much smaller form factor making them perfect solutions for spaces limited PCs without compromising on specifications or upgradability potential like GPUs or CPUs.

However, compared to their ATX counterparts, they may have limitations in terms of cooling potential and expansion options due to less number of PCIe/SATA ports resulting in restricted ability when it comes to custom water-cooling loops or large air cooler installation within tighter builds.

Budget Constraints

The cost of an ATX PC can often be higher than an M-ATX due to the larger size and more advanced features. When attempting to satisfy budget constraints, M-ATX motherboards provide a more affordable option as they are smaller in size and typically utilize less expensive materials.

While further bells and whistles like PCIe slots, RAM slots, etc. may be limited with these boards and less space is available for expansion or multiple graphics cards here, this can work out better for those on a tighter budget who don’t necessarily require the highest performance machine but still need something that will get them by while providing good value for money.

Additionally, their smaller form factor makes them ideal for compact computers such as HTPCs or LAN boxes. While ATX provides greater expandability if your budget allows it could give you more bang for your buck compared to MATX in the long run – ultimately which one is best depends on how expansive you want your PC setup and what adventures (gaming or otherwise) you plan on taking with it!

Micro ATX vs ATX: Common Use Cases

Depending on the user’s budget and needs, both Micro ATX and ATX motherboards can be used in a wide variety of applications such as gaming PCs, home theater systems, and workstations.

Gaming PCs

Choosing the right form factor for a gaming PC can make all the difference when it comes to performance and expandability. Micro ATX (M-ATX) motherboards are becoming increasingly popular due to their compact size, offering similar component options as an ATX motherboard in a more lightweight chassis.

On the other hand, traditional ATX motherboards have greater compatibility with components and receive more support from manufacturers, providing more choices in aesthetics, features, and performance.

However, they tend to be bulkier compared to M-ATX PCs which results in higher costs. When choosing between M-ATX or ATX boards for gaming purposes you should consider factors such as space limitations of your workspace or home setup, future upgrades, and expandability needs if you plan on increasing memory sizes or adding additional add-in cards for example plus your budget constraints too.

Home Theater Systems

Home theater systems benefit from using an ATX or Micro-ATX motherboard as it provides compatibility with modern computers, audio, and video components, providing the user with an immersive computing experience.

With an ATX motherboard, users have more performance options along with greater expandability capabilities for additional hardware. This is ideal for those who want to boost up their entertainment center performance or upgrade components for reference-level audio quality in their home theater system.

However, ATX motherboards take up more space due to their larger size and require more powerful PSUs than smaller MicroATX boards. While they provide great coverage of I/O ports such as USB 3.0 and SATA connectors that can help boosts speeds tech enthusiasts desire alongside better cooling solutions fitted within larger cases, ATX motherboards may be too large for some set-ups where space is limited.


When it comes to choosing the best motherboard for a workstation, two main form factors come into play: Micro ATX (M-ATX) and Advanced Technology Extended (ATX). Each of these types offers its unique advantages and disadvantages, depending on one’s needs.

Both M-ATX and ATX motherboards provide compatibility with components such as RAM, CPUs, GPU cards, etc., but they do differ in terms of size, expandability options, Cooling potential, and space limitations.

Typically speaking, ATX motherboards provide more flexibility when it comes to expansion possibilities as well as better cooling capabilities due to their larger sizes. On the other hand, M-ATX motherboards tend to be smaller in size which makes them suitable for those who have limited space or want a compact setup while also providing ample connectors and slots for most mid-range workstations requiring minimal upgradeability later on.


Micro ATX vs ATX: Pros and Cons

When it comes to the pros and cons of both Micro ATX and ATX, understanding factors such as size, expandability needs, power requirements, and overall budget make all the difference when deciding on which form factor is best for you.

Read more to find out how these two motherboard form factors compare.

Micro ATX: Compact Size, Limited Expandability

Micro ATX, often referred to as M-ATX, motherboards are a small form factor that offers similar component options as ATX motherboards but in a more compact and lightweight chassis.

They measure around 244 x 244 mm compared to the 300 x 200mm for traditional ATX boards. These smaller boards offer fewer PCIe slots, USB and SATA connectors, and may have only one or two M.2 drive mounts compared to standard-size motherboard counterparts which can impact overall performance significantly.

To counterbalance its port limitations, such systems generally provide better power efficiency capabilities with low noise operation when properly cooled allowing users of space-constrained builds to pack in all they need into even the smallest spaces with ample cooling potential kept in mind.

ATX: Larger Size, Greater Expandability

When considering the size and features of a motherboard, it is important to consider ATX as a good option for maximal capabilities. ATX motherboards are larger than M-ATX motherboards, measuring 305 x 244 mm which allows them to have more expansion options.

With this form factor comes increased PCIe slots, SATA, and USB connectors that allow users to have greater connection capability with their devices such as hard drives, optical media drives, and other peripherals.

Furthermore, the large size of an ATX motherboard provides more options for component compatibility which enables users more freedom when they choose parts for their PC build along with better cooling capabilities since there is more space around components that can be used for heat sinks or fan installation.

Which Motherboard Form-Factor Should You Choose?

It can be difficult to decide which motherboard form factor to choose when building a new PC – should you opt for a more compact Micro ATX design or a larger ATX standard? Ultimately, this depends upon your specific needs and budget.

To help you make the best decision possible, several factors need to be considered when choosing between M-ATX and ATX motherboards. For instance, if space is limited then an M-ATX board may suit best; however, if expandability is required, then an ATX board with its greater PCIe expansion slots and SATA/USB connectors could provide the better option.

The power consumption of each type should also be taken into consideration as some components will require more wattage than what is available on certain boards. Additionally, performance requirements such as overclocking capabilities should factor into the equation too.

Finally, keep in mind that due to their smaller sizes, Micro-ATX boards will typically cost less than their small counterparts yet it’s important not to sacrifice quality to save money – always make sure that whatever model you choose has good manufacturer support so that all drivers and updated BIOS versions can be obtained easily increase reliability & stability over time.


When choosing between two form factors for a Micro ATX and ATX motherboard, it’s important to consider the size, expandability needs, power requirements, performance goals, and budget for the build. Depending on these variables, one form factor may be better suited than another.

The downsides of an M-ATX include fewer PCIe slots and limited options for cooling efficiency compared to an ATX board. On the other hand, smaller motherboard enclosures are more compact and less expensive while still providing capable processing speeds and adequate connection ports.

Ultimately each type has its advantages thus deciding which is best comes down to how you plan to use your custom PC build setup.

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...