The Smallest ATX Cases Money Can Buy

Updated July 22nd, 2018 by Headshot Jacob Tuwiner

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Here’s the deal:

If you’re looking for the best (and the smallest) ATX case money can buy, you’ve come to the right place. I’ve procured the ultimate “smallest ATX case” list so you can make the best decisision when purchasing your next case!

Smallest ATX Case Options

When it comes to building a gaming PC, choosing the right case is incredibly important.

Not only are they tasked with protecting your precious components, they must also provide adequate airflow, not to mention they have to look cool!

Finding the smallest full size ATX case in 2018 can be challenging. In an effort to make your life easier, here are the best and the smallest ATX cases:

Case Image Benefits Shop
Corsair Carbide Series 400C
  • Clean Design
  • Superb Airflow
  • Spacious
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Corsair Carbide Series Air 540
  • Compact Case
  • Space Saving Design
  • Fantastic Cable Management
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Cooler Master HAF XB II EVO
  • Small Case, Plenty of Space
  • Perfect for Travel
  • Supports Full-Size CPU Coolers
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NZXT H400i
  • Beautiful Case Design
  • Ships with Three 120mm Fans
  • Constructed with Aluminum Alloy
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Thermaltake Core V21 SPCC
  • Low Profile Case
  • Dual Tempered Glass Side Panel
  • Easy to Use
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Cooler Master MasterBox Lite 3.1 TG
  • Lightweight
  • Tons of Space
  • Sleek Design
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Thermaltake Core G3 Slim ATX Case
  • Slim ATX Case Design
  • Side Panel Window
  • Full-Size with Low Profile
View Lowest Prices

Corsair Carbide Series 400C - $90

The Corsair Carbide Series 400C features an elegant case design and is the smaller, non-inverted version of the Carbide 600C ATX case.

The $90 pricepoint is well placed, especially when compared to other cases of this quality. The 400C looks sleek and refined – even though it’s a smaller case, the interior still supports up to E-ATX motherboards.

Corsair decided to remove the 5.25” drive bays, completely doing away with cutouts for optical drives on the ATX case’s front panel.

If you’re looking for a sturdy case to protect your PC’s components, the 400C should be on your radar. Constructed with a steel exterior, the case is quite sturdy.

Moreover, the large side-panel window allows you to show off the components in your PC. Despite having a minimalistic design, the case is still very attractive.

The case’s dimensions are 18.3 by 8.5 by 16.7 inches, and the case weighs in at 18 pounds (8.16466 kg). Inside the case is spacious, with room for up to three 2.5-inch drives and two 3.5-inch drives.

Despite being a simple case, it still leaves plenty of room for customization. The massive panel window does a great job showing off the internals, not to mention any LEDs you decide to add to your PC.

Overall, it’s a wonderful case manufactured by a reputable company. If you’re looking for a small ATX case, the 400C is a strong contender. At the end of the day, it may simply come down to whether or not you desire 5.25” bays or not – for most (myself included), the lack of 5.25” bays is not a problem.

Corsair Carbide Series Air 540

The Air 540’s cube shaped design definitely sets it apart from other cases.

The chasis was constructed with optimal airflow in mind – those looking to overclock and push their system to its limits should definitely consider this case, especially if they want their components housed in a low-profile case.

The case has a wide outer shell with two side-by-side chambers inside to provide the best airflow possible.

One chamber is for your motherboard and 3.5” drive bays, while the other chamber houses the power supply, solid state drives, and 5.25” bays. Both chambers streamline airflow to provide the best possible cooling solution.

The front of the Air 540 is made of high-quality ABS plastic, but it doesn’t feel cheap or flimsy. In fact, the case’s build quality is pretty good for a case in this price range. The interior is constructed from steel.

As far as size goes, the case is 332mm wide and 458mm in depth.

Despite its small form-factor, the case can house motherboards from E-ATX to Mini-ITX, as well as six drive trays in total. Its ability to house a lot of drives and varying sizes of motherboards goes to show how spacious the case is on the inside, despite being smaller overall.

The case has three 140mm case fans – one is an exhaust fan in the rear of the case. The other two 140mm fans are in the front and serve as the case’s intake. The intake/exhaust configuration draws cool air in, passes it through the case and exhausts it along with any hot air produced by the components.

What’s the bottom line here?

This case seems compact on the outside yet is spacious inside, with superb airflow. Lastly, the case makes it easy to manage cables, making for a truly professional and presentable gaming PC optimized for the best cooling performance.

Cooler Master HAF XB II EVO - $85

Cooler Master’s HAF XB II EVO is a versatile, compact case that is easily converted into an open air test bench.

The case has two 5.25-inch drive bays, two 3.5-inch drive bays, and six 2.5-inch drive bays. The case also has one front-facing 120mm fan, one rear 120mm fan, and one top-mounted 200mm fan.

Similarly to the Air 540, the HAF XB II EVO has two cooling zones optimized for airflow. The case’s drive racks, panels and the main body are all made of steel. The front bezel is made of polymer rather than cheap plastic.

The case has a removable motherboard tray that supports ATX, micro-ATX and mini-ITX motherboards.

A quick look inside reveals the case's two compartments

The case has carrying handles, making it ideal as a LAN box. The case can also be used as an HTPC, gaming PC, or as a test bench. The case is spacious and versatile, ready to handle whatever you throw at it!

A large cutout on the motherboard tray makes installing CPU coolers with large backplates effortless. Moreover, the case provides flexible cooling options, with plenty of room for radiators.

In my opinion, the case has a great look and feel. Both side panels are removable and both have sturdy handles for easy transport.

Moral of the story?

This case is well-built, has plenty of room that provides great airflow, and is incredibly versatile. Its small form-factor and carrying handles make it a great LAN box. The removable motherboard tray also turns this case into a convenient test bench.

NZXT H400i - $150

It’s no surprise that an NZXT case is being featured on this list of the best small ATX cases. NZXT is a well-respected company known for their quality products.

The H400i micro-ATX case delivers the best of both worlds, a perfect cross between mini-ITX and full sized ATX.

The case has fantastic cooling support and cable management, not to mention its beautiful paint job and intuitive design. I’d recommend this case to new builders because it is easy to work with.

Besides this case’s exemplary design, its cooling potential is one of its most notable characteristics. The 400i has plenty of options to mount radiators and custom fans.

You can fit two 140mm fans in the front and top, in addition to one 120mm fan in the rear.

The case supports five drives, but four of them are 2.5” drives meant for an SSD rather than a mechanical drive. The 400i only has one 3.5” drive bay, one of its main drawbacks and something to keep in mind before purchasing.

This case is quite pricey, so I would not recommend it for budget builders. However, it is an incredibly high-quality case – if you have the money, you won’t regret investing in the 400i.

Thermaltake Core V21 SPCC - $57

The Thermaltake Core V21 SPCC is a cube-shaped case that allows you to customize the panels and cooling how you like.

According to Kit Guru:

The cuboid nature of the Thermaltake Core V21 defies expectations and allows you to rearrange the panels and cooling to your heart’s content. Stripping the chassis bare is a quick process as each panel is held on with two thumbscrews. Once the top, bottom and sides are removed you can see the chassis is a simple framework with a riveted motherboard tray. This highlights how much space you have inside the V21 with clearance for a CPU cooler that is 185mm in height, a graphics card up to 350mm in length and a power supply up to 200mm long when you use a bottom fan in the case.

The case ships with a front-facing 200mm fan. The case is also fitted with multiple dust filters to ensure your parts remain clean and funcitonal.

The case looks clean and refined. It is simple, yet elegant. If you’re interested in displaying the components inside, the V21 also has a sizable side panel window.

Considering the quality of the case and its low price, the V21 simply makes sense – in all honesty, it’s a steal!

Click here for a full review of the Thermaltake Core V21 SPCC.

Cooler Master MasterBox Lite 3.1 TG – $45

The Cooler Master MasterBox Lite 3.1 TG may not be as low cost when compared to ultra budget cases, but it really gives you a great bang for your PC gaming buck.

The case has more room and better features than many of its competitors, which is why I decided to include it on this page. Despite being a micro-ATX case, it still has sufficient space for even some of the largest graphics cards and CPU coolers on the market.

The case looks great – it can support micro-ATX and mini-ITX motherboards, and is constructed primarily of steel and sturdy plastic. The case weighs in just under 9 lbs, making it quite lightweight.

The case doesn’t make any conscious effort to stick out too much, but its simplistic and stylish design still catches one’s eye.

The left side panel is entirely clear, allowing you to show off your components. Although, if you’re not one to properly manage your cables, you probably want to steer clear of this case – on the other hand, poor cable management constricts airflow anyway, so it is best to keep your cables nice and tidy.

It’s no surprise that another case by Cooler Master made the list – this time around, they are providing a fantastic case with a spacious interior and an awesome design, all for an affordable price.

Click here for a full case review.

Thermaltake Core G3 Slim ATX Case - $70

The second Thermaltake case on this list is the Core G3 Slim ATX Case, which is also the second case from Thermaltake’s Core series.

In recent years, Thermaltake has produced many cases that are largely popular, especially their Core series. The Thermaltake Core G3 is no exception!

The Core G3 is a full-sized ATX case with a slim design, perfect for small spaces. The case supports both ATX and micro-ATX.

Thermaltake’s Core G3 also has a nice side panel window. The front panel has 2 USB 3.0 ports, 2 USB 2.0 ports and one HD audio slot.

The case doesn’t include any case fans, which may be seen as a drawback for some – although, it has plenty of room for you to add your own custom fans.

It features four drive bays in total, two of which are 2.5” bays and the other two are 3.5” bays.

This case offers a stylish full sized form factor without being too big and bulky. It’s one of the best (and the smallest) ATX cases money can buy!

Case Buying Guide

Carbide Air 540

If you’re interested in building a gaming PC, it is imperative that you choose the right case. Of course, that’s easier said than done.

In an effort to aid those new to building gaming computers, I’ve created this guide to help you understand everything you need to know when it comes to selecting the best ATX case.

So, what’s the deal with ATX, micro-ATX, and mini-ITX?

The names stem from motherboard size categories. Motherboards are grouped into these three categories.

ATX is the largest, micro-ATX is a bit smaller, and mini-ITX is the smallest.

At the moment, full-sized ATX cases are the most popular form factor for a variety of reasons. ATX motherboards are 12 × 9.6 inches (305 × 244 mm). ATX cases are usually also compatible with micro-ATX motherboards, which are 9.6 × 9.6 inches (244 × 244 mm).

Lastly, mini-ITX motherboards are 6.7 × 6.7 inches (170 x 170 mm), making them the smallest of the three form-factors.

Since cases are responsible for housing motherboards, cases are categorized in the same manner (ATX, micro-ATX, etc.) It’s always important to ensure that the case you want is compatible with your motherboard’s form factor.

A Great Case Is…

1. A great gaming case is strong. Avoid cases constructed with flimsy plastic – after all, your case is supposed to protect your parts and keep them from breaking, right?

A few plastic parts here and there are okay and most cases have some plastic. However, ensure the plastic is strong and of high quality before risking your expensive components.

2. A great gaming case has fantastic airflow. If your case doesn’t have good airflow, your PC could overheat and shut down. Despite being able to handle high temperatures, your parts can become damaged if they are too hot. Airflow is incredibly important!

You may find this PC airflow guide helpful:

3. A great gaming case has room for plenty of quiet case fans! This goes hand-in-hand with airflow. If your case doesn’t have space to add case fans, it’s a no go.

Thermaltake Core G3

Most gaming cases ship with fans included – many of them have cool looking LEDs too. But before you’re fooled by fancy lights, it’s important to make sure your fans are quiet. Noisy fans can be especially annoying if you’re sensitive to noise.

4. A great gaming case has enough room for your components! This may seem obvious, but some cases don’t have enough room for CPU coolers and graphics cards. For example, the first time I built a gaming PC, the hard drive bays in my case got in the way of my graphics card!

5. A great gaming case has good cable management options. This means there is plenty of space for your cables, and they can be run throughout the case in a neat and orderly fashion. Instead of bundling them up inside the case – which is both ugly and bad for airflow – you can run your cables in the back. This keeps your case looking clean and promotes good airflow.

Before you pull the trigger on the case of your dreams, make sure that:

  • Your graphics card will fit inside the case
  • Your CPU cooler will fit inside the case
  • Your case has enough hard drive bays

Otherwise, you’ll be quite disappointed!

Do You Need a ‘Gaming’ Case?

Many companies advertise their cases as “gaming cases”. Just because a case is outfitted with cool LED lights does not necessarily make it a gaming case.

Most uneducated customers will buy a case simply for its looks, without really considering the factors mentioned above. It is more important to find a functional case that provides good airflow and cable management. A good case must also be sturdy and cost effective.

Sure, a good looking case is always nice, but it is not necessary. If you’re on a budget, especially a budget below $500, don’t spend more than $50 on your case. In fact, I’d recommend spending $40 or less.


Don’t be fooled by advertisements and flashy lights. A great case is sturdy, provides good airflow, has a spacious interior, etc.

Of course, the more you pay, the higher quality case you’ll have. Nowadays, there are so many case options to choose from it becomes overwhelming.

It is a way to show off your personality – at the same time though, it’s important to buy a case that’s functional. If you are building a new gaming PC on a tight budget and you have an old computer laying around that you don’t use anymore, don’t be afraid to tear out the old parts to reuse the case!

At the end of the day, the your PC build comes down to your budget, your personal preferences, and what you’re looking to do with your PC. That’s the beauty of PC gaming – you can tailor your PC to suit your needs!