5 Best Smallest Micro ATX Cases in 2021 (Reviews & Buyer’s Guide)


In this techie world, everything is evolving with a high speed. Be it any field, just name it and see how smart things are going on. Nowadays, people are no more going with the standardized cases, new cases such as Mini-ITX and Micro ATX are ruling over the market.

Undoubtedly, no more stress over the standardized cases. On one hand, Micro ATX is the new boon to industry likewise, people are hesitating to switch to these newbies as both these techies Micro ATX and Mini ITX are not capable of adopting any sort of updation.

The high advantage of micro ATX is its portability. Indeed! Micro ATX is highly portable. Micro ATX and Mini ITX is just like a new birth to the standardized cases. The upgrade they’re coming up with is literally remarkable. With the all-new updated GPUs, Micro ATX is a must to have in this technical era.

Herein, we’ll be throwing light on the best smallest Micro ATX cases in 2021. Generally, there are two categories for the cases- simple & dull while the second category is the pleasant & vibrant. There are people who loves colors, basically the looks if we talk about the vibrant cases but on the other hand, comes the ones who have no interest with the looks.

5 Best Smallest Micro ATX Cases in 2021

Time to dive in to the list of the best smallest Micro ATX cases reviewed in 2021-

  1. Cooler Master MasterBox Q300L Micro-ATX Case
  2. Silverstone Tek SG10 Micro-ATX Case
  3. Corsair Crystal 280X
  4. Cooler Master Silencio S400
  5. NZXT H400i

1.Cooler Master MasterBox Q300L

The magnetic designed dust filter Cooler Master MasterBox Q300L is available on Amazon at the best price of $49.99 with no shipping charges at all. The MasterBox comes with a transparent acrylic side panel with adjustable I/O & fully ventilated airflow.

Cooler Master MasterBox Q300L is available in Black color. It weighs only 1.1 pounds. The exact dimesions of the MasterBox- 15*9.05*15.23 inches.

Coming on to its I/O panel, the panels offers you 6 adjustable different locations as well as the adjustable positions either vertical or horizontal. For a full view inside, the MasterBox comes with an edge to edge acrylic transparent side panel.

Cooler Master MasterBox Q300L is quite smaller in size but when it comes to the performance, there is no match and hence, ensures high portability. There are two things that the company has to offer- modularity and thermal performance.

The amazing design and its beauty makes it even more elegant and a must to be picked up to your bucket. MasterBox is well-known as the best affordable micro ATX case.

Cooler Master MasterBox Q300L has an installed LED fan. The micro ATX MasterBox is quite powerful and doesn’t make any noise.


  • Material quality is not up to the mark
  • Ports are loose
  • Cooling procedure is not so good
  • Customer reviews are just okayish

2.Silverstone Tek SG10 Micro-ATX

Silverstone Tek SG10, the high-end micro ATX case ensures robustness and reliability. The colors available in Silverstone Tek SG10 are white and black. There is no compatibility issues and the case is compatible with both micro-ATX and mini-ITX boards.

The case is absolutely affordable as its made from plastic and hence is not expensive. Silverstone Tek SG10 has 2 audio and 2 USB 3.0 ports. Coming on to the cooling system, the Silverstone Tek SG10 Micro-ATX has two fans, one 80 mm and the other one is 92 mm.

Apart from these, Silverstone Tek SG10 also has 2 fan slots- one 120 mm and the other one is 80 mm. The case comes with the PS2 ATX power supply, a cable routing system, and unlimited PSU allowance. Not only this, the Silverstone offers an expansion card that is compatible with 358 mm or 144 mm.

CPU cooler height is 140 mm and the case is compatible with the Kensington locks. Silverstone Tek SG10 comes with the dust filters already installed in it. Making it an easy installation of the motherboard, the case features CPU backplate cut-out.

With Silverstone Tek SG10, you really need not to be worried about the flexibility and affordability. This is the best case for gaming when you’re looking for something affordable.


  • Though Silverstone Tek SG10 comes with a cable routing system, lacks good cable management.
  • Cooling System is not satisfactory.
  • It’s difficult to open or close the case once installed.
  • Side panels takes a lot of efforts to get removed.

3.Corsair Crystal 280X

Corsair Crystal 280X is considered to be the best case in the list of the best smallest micro-ATX cases reviewed in 2021. The case has been designed using steel, plastic, and tempered glass.

Since Corsair Crystal is the best overall, the case has no compatibility issues and can support both Mini-ITX and Micro-ATX. The case also features side-panel windows. There are 4 expansion slots available in the case. The exact dimensions of the Corsair Crystal 280X is 15.67 * 10.87 * 13.82 inches.

With its cubic style chassis, Corsair Crystal 280X is well known for its design. And, honestly this is the best mATX case in the retail arena. To all the black lovers, Corsair Crystal offers you an absolutely all-black look with its tripe-sided glass paneling.

Moving on to the interior of the Corsair Crystal 280X, the case provides you an amazing compatibility with a Mini-ITX motherboard. There’s an ample of space in the interior designing part that makes the fans work even more efficiently.

One of the impressive features of the Corsair Crystal 280X is its dual-chamber layout and hence making it a good fit in the GPU units. The case allows you fit in the coolers easily up to the 5.9 inches in height.

Not only this, there are a total of 6 cooling fans each of 120mm. The cooling fans are responsible for the minimum dust build-up. Also, there are 3 radiators each of 240mm responsible for liquid cooling options.

If you’re building up your PC for the very first time, this is the best mATX case to go with with literally no second thoughts, be it about its dual-chamber layout feature or zero wire tangles or its interior components placement, the case is just perfect!

Herein, you’ll get a rear chamber to place all your wires and cables. In terms of storage, Crystal 280X offers you 5 internal bays to work as per your preference and requirements.

Are you the one who believes in personalization? With Corsair Crystal 280X there’s nothing that you cannot do. For personalization the case, you have LL 120 corsair RGB fans and 32 colorful LEDs. Along with this, the mATX also offers you the Node Pro digital controller to modify the designs and personalization of, course.

For the internal association, the mATX has the side panel window. You can also go with the non-RGB variant to keep it in the budget. As the case has a chassis structure, it weighs around 15.65 pounds. With the 4 expansion slots available, you can connect sound cards, wireless adapters, and much more.

There are 3 dust filters positioned at the front, roof, and even the floor of the case to control dust. Corsair Crystal 280X is designed in such a way that it is capable of providing the cool air even to the small hottest components.

The mATX provides you 2 USB 2.0 slots for microphone and speaker output. Overall, there are no flaws at all and Corsair Crystal 280X is literally the best mATX cases listed above especially for the first time PC builders.


  • Type-C port is not available
  • Thermal performance is average

4.Cooler Master Silencio S400

The best quiet case available at $89.99 made with steel and plastic. Cooler Master Silencio S400 offers you a power supply of 350W. The mATX case is compatible with both Mini-ITX and Micro-ATX. There are a total of 7 expansion slots available. The exact dimensions of the case is 8.27 * 16.46 * 16.06 inches.

There’s no side-panel window with Cooler Master Silencio S400. The mATX case is popular as one of the best silent mATX cases. With this mATX case, users get access to the ventilated top panels and the sound dampening cushioning that’s responsible for a whisper-quiet usage.

Though the case doesn’t feature side-panel window but to cover that thing, Cooler Master Silencio S400 has the reversible front cover. There are a total of 7 radiators- four at the front, two on the top, and one at the rear.

Coming on to the storage of the Cooler Master Silencio S400, the mATX case has 4 slots for HDD and SSD expansions each with ODD storage unit. HDD cage is the remarkable feature of the Silencio S400 that is quite flexible and can be shifted back to incorporate the radiator as well as can be moved to the front to fit in a PSU.

For a mind-blowing noise free experience, Cooler Master Silencio S400 is the best mATX case reviewed in 2021. Rubber padding is responsible for this stunning noise free thing. With Silencio S400 and actually with all these mATX cases, you need not to buy any extra fans. The fans are preinstalled in the cases. The Silencio S400 mATX case has two 120mm fans.

With all these features, Silencio S400 also offers you the front and top-most ventilation. The mATX case not just comes with the mounting system with the reversible support but also, the case has a fusion of rubber stompers and magnets.

For connecting wireless cards, adapters, sound cards, and many more, Silencio S400 has a total of 7 expansion slots. With 7 expansion slots, the case provides you two USB 3.0 ports that are comparatively faster than the USB 2.0 ports.

Cooler Master Silencio S400 has a combo jack that allows you access the audio-cum-microphone functionality. You can even expand the storage using the front card slot on the SD card. The mATX case weighs 15.5 pounds.


  • Thermal Performance is average
  • Type-C port is not available

5.NZXT H400i


NZXT H400i is entirely made up of steel. There’s no plastic and tempered glass used while designing. The maximum power supply of the mATX case is 400W. Just like all other mATX cases listed above, NZXT H400i is also compatible with both Mini-ITX and Micro-ATX motherboards.

There are a total of 4 expansion slots available with NZXT H400i. This mATX case is considered as the premium choice over all others. The case is available at $150. If you’re concerned for the cooling features, there’s no choice better than this mATX case, NZXT H400i.

The mATX can easily incorporate with the 5 available fans. So, definitely, you don’t need to go for the separate fans as NZXT H400i is already providing you with the package and that includes 2 front-aligned, AER F120 modules each with one rear-ended AER F120 fan.

NZXT H400i supports water or liquid-cooling feature that makes it a convenient option for your device and you can easily handle games like Cyberpunk 2077, Fortnite, League of Legends, and many more like this. With the radiator support, the NZXT H400i provides you a space for 3 unites, 2 for the front and 1 for the rear.

Not only this, the mATX also has front panel filters that works as the air supply intakes and hence thermal performance is amazing. The mATX case has PS/2 power supply that is cherry to the cake.

The major highlight of the NZXT H400i is its modern layout that offers you CAM-based, smart device integration. With this mATX case, you’ll be able to access the fan temperature control and RGB lighting modulation along with the V3 digital controllers.


  • No Type-C ports
  • Fans are a bit noisy but for that you can turn on the noise reduction

Summing Up

This is all about the 5 smallest micro-ATX cases and all these cases are compatible with both mini-ATX and micro-ATX motherboards. Generally, there are three categories of mATX cases- Micro ATX, Mini ATX, and standard ATX motherboards. All these cases varies when it comes to the dimensions.

  • The Standard ATX dimensions is- 12.0″ * 9.6″
  • The Micro-ATX dimensions is- 9.6″ * 9.6″
  • The Mini-ITX dimensions is- 6.7″ * 6.7″

You can use a micro ATX case for both the micro-ATX and mini-ITX motherboard but neither micro nor mini can fit into the standard ATX motherboards.
Here are some of the features to considered while buying a mATX case- design & customizations, cooling options, noise, dust filters, space for components, durability, and of,course your budget!


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