What is the Smallest ATX Case & How to Choose best One

ATX is the most demanding form factor of PC cases that are now recognized as the standard for user-friendly builds. The most important and usual components that take place in a PC building process is a motherboard, which is the main ingredient for a working PC that can live up to your expectation. Just like other components motherboards have different standards for form factors.

From all the formations the most recognized formate is the ATX form that is standard for modern PC building, other than that there is Micro-ATX, Mini-TX, Nano ITX, and Pico ITX form that is useful for most compact PC builds that are small in size and can place in compact locations where you have problem with large and bulky builds.

In this article we will understand What is the Smallest ATX Case? and How it is common for modern PC building for professional and personal experience. We will discuss the convenience of the ATX system over other form factors with equivalent motherboards that make understanding easy for the recognition of the building of a perfect system.

What is the Smallest ATX Case?

The Advanced Technology eXtended motherboards are known as ATX, they are developed as the old desktop replacement from Intel in 1995. The older known designs for desktop PC are AT form factors. These designs share the same looks for a long line of generations and at the end of 1996, everything is changed with ATX standards PC enclosures.

Now ATX is the new standard for PC cases invented by Intel corporates that are considered the first major leap in the layout of PC motherboards with a vertical orientation of 90 degrees. The new board is fixed vertically and rotated. It makes cable management easy and allows more room for big GPUs and power supplies with effective use of space.

The new ATX motherboards bring new ATX cases which also brings the advancement for CPUs end. That Intel fillup with the new generation of processors that are faster than last year. Due to the improvements on each part, the latest ATX form factor becomes the choice of both the commercial line for business and home PC builders.

The new improvements are stabilizing in the industry with interchangeable parts, mounting points, I/O panel replacements, and tested with various power supplies for more beefy and powerful components. The results were surprising and introduced new connectors for motherboards which increase the hipe of ATX computer designs.

After the success of ATX motherboards, Intel continues the work of development and comes up with a BTX (Balanced Technology eXtended) design that is introduced in the year 2004. Intel considers the new BTX a standard interface for future PCs but soon drops the sentiments as very few manufacturers adopt the new design.

It makes Intel discontinue the BTX form factor and stays with the currently available ATX as the standard size for home and commercial PCs. you can say that the BTX could stand the intention against the ATX as a replacement. The BTX is closed by Intel in the year 2006 and keep the thrown for ATX form factor that still doing great for personal computers in 2021.

Motherboards Form Factors

ATX Standard PC Enclosure’s

ATX is a wildly used motherboard design with the dimensions of 12×9.6 inches and (305 × 244 millimeters), it allows many MATX mothers to take place in standard ATX due to the slight size changes. It brings more acceptance for ATX chassis with microATX motherboards.

Besides ATX standard there are various other formates for smaller forms that are good for compact personal PCs. The smaller motherboards include Micro-ATX, FlexATX, Mini-TX, Nano ITX, and Pico ITX. These are all the smaller designs other than standard ATX which is the best for gaming rigs and intensive editing machines.

The smaller form factors you’ll see are not the most common in the building of high computing powerhouse machines. Those are capable of gaming, editing, 3D designing, graphics developments, and rendering art effects. Other than that Micro-ATX and Mini-ITX are essentially used for home theatre PCs due to their small compact size.

Despite its different names, ATX motherboards have differences in dimensions, even a standard mother comes in a variety of sizes that make it equivalent for multiple cages. Due to the large size of standard ATX motherboards, the largest types have the most expansion slots and very compact dimensions. So they’re capable of supporting MicroATX and ATX.

MicroATX Enclosure’s

Micro-ATX motherboards bring fewer new upgrades from the standard ATX version and continue the legacy with a little compact design is known by Micro ATX. You can consider it a little smaller version of ATX motherboards and even fit in ATX standard PC case. But unlike the traditional standard ATX tower cases the mid-tower cases are usually bound to the popular micro ATX and mini-ITX motherboards.

They offer a nice build that is compact and powerful without compromising the very little space. The thing is M-ATX cases are the perfect fit for micro ATX motherboards that are typical for their league. The cost is quite less than the comparatively much smaller mini-ITX motherboards and their relative PC cases.

Although microATX is a bit smaller than ATX it has become very popular for a variety of uses in both the commercial and home entertainment experience. From the year 2009, the compact microATX become a high-end segment for 9.6×9.6 inches dimensions that are not more than the (244×244mm) diameters.

FlexATX Enclosure’s

The FlexATX is a motherboard form factor that is the descendent of ATX standard. It was released in 1999 by Intel in remarks of a microATX subset motherboard with the same caliber mounting and I/O that resembles the micro ATX but has a very compact design that is unlike microATX.

FlexATX can equip a 9×7.5 inches dimensional motherboard that is no longer than the (229×191mm) size. This complex design becomes the military choice for the increasing number of expansion slots and portable design that is easy to carry around in a rigid casing.

In terms of power carriage, a FlexATX case can have a micro ATX PSU that is smaller than a standard ATX PSU and easily fit in the small dimensions of FlexATX cases that will host it for the greater good. It is a new generation of air-cooled enclosure that is exclusively for commercial and industrial applications.

You will find FlexATX in the deployment of defense systems under military supervisions that use its compactness for the portable rackmount servers, projects developments, maintenance, communications, and many other logistics of military systems.

Mini-ITX Enclosure’s

The Mini-ITX motherboards are much shorter and compatible with small form-factor cases that are relative to the width of 6.7×6.7 inches that is not more than 170×170 mm in diameter. It is the biggest size difference from the standard ATX PC cases and has been improving with new technology.

Each size of the motherboard determines what PC case you can get for what kind of performance. The development of Mini-ITX was introduced in 2001 by VIA technologies, and since it is the smallest of all form factors with the most narrow expandability that has minimal power consumptions.

In comparison with the standard ATX, the MicroATX is much different with fewer PCIe slots and supports less RAM than the standard ATX, which is the motherboards allow users to add more components like multiple GPUs, and multiple hard drives, optical drives, and many other additional increments for the benefits.

Being shorter in both height and width makes micro-ATX motherboards fit in very compact cases that are smaller in size. Mini-ITX typically costs less and is comparative useful for very different scenarios, due to the small form they fit any small desk for casual work, CCTV recordings, automobiles developments, home setups, and featuring controls for network devices.


However, there are many other form factors than the standard ATX, but the use of ATX is ideal for all sorts of commercial and home platforms. The compact ATX cases are considered very much new for gaming builds and enhance a system with a vast range of PC components. The benefits of each ATX are different other than standard ATX and MicroATX every other ITX’s are meant for small working capacity that will function in the small area, while the powerful gigs are bound with ATX and MicroATX chassis that is stable in extreme computing.

FAQS about Smallest ATX Case
What is the smallest ATX?

ATX is a PC motherboard with 12×9.6 inches dimensions and 305mmx244mm diameter. Such motherboards fit in an ATX PC case with the same dimensions. The smallest among all the ATX is the Lian Li O11 Mini PC case that has wonderful cooling capacity and space for multiple water cooling radiators without compromising the efficiency of other PC components. It can fit in a very compact space in the office and home with beefy hardware that has the right amount of power for all the workloads that you want to do with a small PC.

Why would you need an ATX motherboard?

It is based on your needs if you prefer a little small and compact PC build that is possible with an ATX motherboard that can provide better upgrades, multiple PCIe slots, RAM, and more. When building a powerful computer and under budget, ATX motherboards are a perfect choice for a compatible modern PC that can do more with less spending,s. You can pair an ATX motherboard with a small form factor smallest ATX case for the best compact PC building that is convenient and customizable for everyday computing.