How to Choose a PC Case

The Form Factor spec gives the case's class, such as full tower, mid tower, Micro-ATX or small form factor. Motherboard Support lists the board sizes it takes. A bigger case takes smaller boards, so a case that takes ATX also takes Micro-ATX and Mini-ITX.

External Volume, in litres, is the easiest way to compare how much desk or floor space two cases take. A mid tower suits most builds; a small case looks neat but limits the graphics card, the cooler and the power supply you can use, and is harder to build in.

Three numbers decide whether your parts fit, and every one is on the case maker's specification page.

• Max GPU Length: compare it with the graphics card's Length. Front fans or a front radiator usually take some of this space, and the case maker often gives the figure both with and without them.
• Max CPU Cooler Height: compare it with the air cooler's Height.
• Radiator Support: the radiator sizes the case takes in each position, such as 360 mm at the front and 240 mm at the top.

A case's job is to let cool air in and warm air out. A mesh front panel lets in far more air than solid glass or plastic, and usually means lower temperatures and quieter fans for the same parts.

Fans Included says how many fans come with the case. Many cases ship with one or two, which is often not enough for a powerful graphics card. The usual layout is intake at the front or bottom and exhaust at the back or top. Dust filters on the intakes keep the inside clean, and ones that slide out are much easier to keep clear.

Dual-chamber cases, with glass on the front and side, usually take their intake fans at the side or bottom instead. They can cool well, but check where the fans go before you buy.

Tempered Glass and Side Panel tell you what the sides are made of, and Colour what finish it comes in. Glass shows off the parts but is heavier and can break if the panel is dropped. Solid panels, especially with sound damping, can make a quieter PC.

Many modern cases have few or no 3.5 inch bays, because M.2 SSDs need none. If you keep hard drives for storage, check the 3.5" Bays spec. Our SSD guide covers the drives themselves.

Most cases take a standard ATX power supply; small ones may need SFX. A long power supply can clash with drive cages in the bottom chamber, so check the case's maximum power supply length if it gives one.

A front USB-C port only works if the motherboard has the matching internal header, so check both. The same goes for any extra front USB ports: each needs a header on the board to plug into.

• Space behind the motherboard tray for cables, with tie points and grommets to route them through.
• A cover over the power supply, which hides its cables.
• Removable dust filters and drive cages.
• Support for back-connect motherboards, if you want one with its connectors on the rear. These only fit cases made for them.

Our build guide walks through putting the parts into the case.

Small form factor cases make a PC that fits on a desk or under a TV, but every part has to be chosen around them.

• Graphics card: check thickness as well as length. Many small cases take a card of two or two and a half slots, and some large cards are thicker than that.
• Cooler: often a low-profile air cooler or a small all-in-one, so a very hot processor may run slower than it would in a bigger case.
• Power supply: many need an SFX unit, which costs more than ATX for the same wattage.
• Building: there is little room for hands and cables, so expect it to take longer. Modular power supply cables help a great deal.

• Entry level: a case with a mesh front, dust filters and at least two fans does the job well.
• Mid-range: better airflow, more fans included, more room for cables and radiators, and more tool-free fittings.
• High end: better materials and finish, more size options and features such as modular layouts.

A case only changes performance through airflow. If the budget is tight, spend on airflow and fans before glass and lighting.

• The PC cases category can be filtered by Form Factor, Motherboard Support, Side Panel, Tempered Glass and Colour.
• Will it fit? checks a graphics card, cooler and motherboard against a case and marks each one fits, does not fit or unknown. Unknown means the case's listing does not state that clearance, so check the maker's page.
• The PC builder warns when a graphics card may be too long for the case, using the typical clearance for the case's size where the case does not state its own.
• Case fans if the case comes with too few.

Each product page shows the price at the shops we track and its price history, with a bell to set a price alert.