Buying a Case: Drive Bays, Form Factor and More

Buying a Case: Drive Bays, Form Factor and More

Buying a case is an oft-understated part of building your own computer, but the case you choose is actually quite important.

Here are the main reasons:

  • Different cases manage airflow differently (which is important to prevent the overheating of your components).
  • Different cases are made to suit different form factors and storage capacities.
  • Different cases look quite a bit different, and you want to choose one that’s at least slightly aesthetically pleasing to you.
  • Finally, your case is one of the biggest factors of your building experience. Case too big? Might have issues with cabling being too short. Case too small or doesn’t have cable management features? Enjoy the tangle of heat-conducting electrical cables you’ll have surrounding all your components. (Don’t. Cable management is important, and that is bad.)

There are a multitude of factors to take into consideration when buying a case for your computer. We’ll get into those now.

Form Factor Support and Size


Above is the Fractal Design Define R5. Does that case name sound like a bundle of nonsense words, letters and numbers? It sort of is, but the Define R5 is considered one of the best cases on the market right now.

The reasons for this are apparent in the image above: a large amount of drive bays, a massive size to work around in, removable drive bays, and a lot of drive cages. There’s more than that, of course, but the main appeal of the case is advertised clearly in the image above. However, there are a few major downsides to this case: its sheer size (which can be overkill for many builds), its weight (due to the quality of the build) and, finally, the high price point. Seriously, this thing costs $130 on Amazon. It isn’t cheap.

Anyways, the motherboard you buy (more on that in another article), will have a form factor. Common form factors include ATX, mATX and mITX – most cases will support one or many of these. ATX, a dominant form factor, is the largest of the ones listed, its primary features including more PCI-E slots and more ports on the back. (There is technically other larger form factors, but those are more for server-grade and crazy-enthusiast hardware.)

Let’s go over the main case/motherboard form factors.

  • ATX cases will support ATX, mATX, and sometimes even mITX, though having anything smaller than an ATX motherboard in an ATX case is silly.
  • mATX cases will support mATX and sometimes mITX but not ATX. These are usually for smaller builds, though not the smallest.
  • mITX cases will only support mITX boards and are the smallest of the bunch.

Essentially, the larger the case/motherboard is, the more room you have for expandability further down the line. For instance, mITX and mATX boards will typically only support one dual-slot graphics card, but ATX boards can have two, three or more. Make sure you get a case and motherboard that support your needs.

In general, unless you’re using a particularly large amount of peripherals and multiple graphics cards, an mATX board and case will serve your purposes perfectly fine. I happen to have an ATX case with an mATX board.

Expandability (Drive Bays, etc.)


When buying a case, you’re going to want to keep an eye on how many drive bays and drive cages it has. On an ATX case and most mATX cases, this shouldn’t be a problem; in fact, most consumers will find the amount of drive bays to be sheer overkill. While this may be the case for some of you, people using multiple drives in a RAID array will definitely want a case with plenty of room for drive bays.

In addition, you may want removable drive cages. This is particularly beneficial for gamers when buying graphics cards, as some can be particularly long and don’t easily fit into most cases.

Pay attention to your case’s dimensions when buying it. Most cases will have room to mount what are considered “long” graphics cards (which can be up to twelve inches or more), but make sure that you aren’t buying a case too small to support the hardware you’ll be packing in it.

Aside from clearance for cards and bays for drives, there shouldn’t be many other concerns for expandability. Let’s continue to airflow.

Airflow (Fan Mounting, Size, etc.)


When buying a case, you want to watch for places to mount fans. The more fan mounts on a build, the better.

Most cases you buy should already have at least one intake and one exhaust fan already mounted, but be sure to check anyways. If the case you’re buying doesn’t include fans, you need to buy some, otherwise you’re just about guaranteeing that your parts will overheat, and you really don’t want that.

Also, if you’re interested in a liquid cooling solution, you’ll want to make sure that there is a compatible dual-fan slot on the top of your case to mount a radiator. Of course, if you’re going to liquid cool your CPU, you probably already knew that!

Extras (Cable Management support, etc.)


In the world of computer building, good cable management is considered the mark of a master builder. In addition to making everything look so much more clean and elegant, good cable management also makes maintenance easier and should prevent the accumulation of dust and heat, neither of which you want to have in large quantities inside your computer.

The secret to good cable management isn’t purely skill, though. The main secret of good cable management is having a good case. So make sure you buy a case that has cable management holes and plenty of room in the back for your cables to run through. In addition to the aforementioned benefits, good cable management will make the building process itself easier, too, so make sure you don’t forget it.

Aside from cable management, other case features you should keep in mind are things like:

  • Included fans. This isn’t so much an “extra” as a cardinal sin to not have. A case without included fans is a disgusting thing.
  • Onboard USB3 Headers. I’d recommend not going without these. Come on, it’s 2015. (At least it was when I wrote this. The longer it takes for you to read this, the more this applies.)
  • Removable drive bays/cages. Remember how I talked about those earlier? They’re still important. You want a case that’s as flexible as possible for your needs.
  • Integrated power supplies. Actually, most of these aren’t dependable. Be sure to check reviews before buying a case with an integrated power supply – it usually is not worth the trouble.
  • More! Some boutique cases include things like temperature monitors or LCD screens that can be mounted in your drive bays to monitor and change things like fan speed, case lighting and more.


Keep all these things in mind when you’re going to buy yourself a nice little case, and you should be all set.

Anything you feel like I should’ve mentioned or went into more detail on? Anything you’d like to add? What case are you using? Say something in the comments, and let me know!

Christopher Harper
Christopher Harper

I'm a longtime gamer, computer nerd, and general tech enthusiast.

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