Today’s PCs come in enough shapes to dazzle a dodecahedron, but in the realm of desktops, three main classes of aftermarket PC case reign supreme: full ATX, MicroATX, and Mini-ITX. These three case “form factors” make up the bulk of the market for chassis, and you can simply think of them as big (ATX), medium-size (MicroATX), and small (Mini-ITX). Each of the form factors has its own strengths and weaknesses; in this guide, we’re going to go compact and focus on the Mini-ITX ones.
These cases exude sex appeal and intrigue, teasing the idea of a powerful PC in shoebox or smaller size. They also show the most originality—and the least adherence to standardization—of all the kinds of PC case. Let’s see what makes Mini-ITX as a concept, and the cases that use this form factor, stand out, and steer you to some of the best examples that we’ve built PCs inside.
What Is a Mini-ITX Case?
The benefits of a Mini-ITX form factor PC are straightforward. Mini-ITX cases are smaller than the rest of the pack, and in some workspace or living-space scenarios, tiny is better by nature. In particular, a Mini-ITX PC is often the best option in offices where space is at a premium: say, as a laptop alternative for people working at common tables, or in cramped cubicles. (No, this hasn’t been a thing for the last year or more, but plenty of us have home offices we wish were far less cluttered.)
Unlike chassis in the larger MicroATX and ATX sizes, many Mini-ITX PC cases can sit comfortably on desks, in niches, on shelves, or under a monitor without being obtrusive. Some are even designed to mount behind monitors or under desks to hide them from view. The Mini-ITX case isn’t bound by a strict size limit; what makes a case Mini-ITX is its support for the Mini-ITX motherboard form factor, and none larger. (More on that in a bit.)
It would be unwise to judge the potential of Mini-ITX PCs and cases solely by their size, though. The amount of processing power they can host doesn’t scale up and down 1:1 with the cubic volume. Indeed, much depends on the individual design. For example, today’s big, legacy-style ATX towers tend to allot plenty of space for stacks of hard drives or big liquid coolers that most PC users will never install. Most Mini-ITX systems allow you to install standard desktop motherboards and socketed desktop CPUs, and under the right conditions can be just as powerful as a kitted-out ATX tower.
That’s not to say that there aren’t limiting factors—physics still applies. The major drawbacks to a Mini-ITX build lie in two main areas: the amount of interior space, which can limit what you can fit inside the chassis, and the thermals and cooling, which encompass the chassis ventilation, any fans installed (or that you can install), and the CPU and GPU you choose.
Let’s start with the space issue. Mini-ITX cases come in more unusual, one-off shapes and sizes than other kinds of PC cases, but their one unifying aspect is the class of the motherboard they accept. As noted earlier, the Mini-ITX form factor defines both a size class of motherboards, as well as the cases that fit those boards.
Mini-ITX motherboards measure 6.7 by 6.7 inches, with mounting holes in prescribed locations; Mini-ITX cases, then, are built around accommodating these board dimensions. That said, some Mini-ITX cases are much bigger than others in terms of height or volume. But by definition, a “true” Mini-ITX case won’t accommodate any board bigger than a Mini-ITX one, with the exception of a few that also support the slightly larger (and uncommon) Mini-DTX form factor. Mini-DTX boards are slightly taller than Mini-ITX boards, at 8 by 6.7 inches. (The next biggest size class for motherboards, MicroATX, is 9.6 inches square and defines the next-largest class of PC cases.)
The compact nature of Mini-ITX cases and their associated motherboards usually doesn’t leave much room for other components, lots of drives or fans, big cooling gear, or other parts. Mini-ITX motherboards can house only two RAM DIMMs and a single PCI Express x16 add-on card. Depending on the design of the case, the PCI Express card support might be limited to a half-height, single-slot card, but some Mini-ITX cases can hold full-height, beefy dual- or triple-slot graphics cards without any issues. It all depends on the design, and that is why it pays to scrutinize a case’s specs (and read reviews) before buying.
The Limits of Power: Cooling Fans, PSUs, and More
A whole host of other variables also limit what you can and can’t put inside a Mini-ITX system. Some of them have nothing to do with the Mini-ITX case itself.
Take the Mini-ITX motherboard. Some are limited in how much power they can handle, or cap the power draw of the CPU you can install. Depending on the mobo, you may have a top allowable TDP rating of, say, 65 watts, though this is far from true for all Mini-ITX boards. Plus, to cool the CPU, depending on the chassis design, you may be forced to use a low-profile fan cooler similar to the small stock coolers that AMD and Intel provide with their mainstream desktop CPUs. In some cases, it’s possible to add larger air coolers, but again, this varies from one chassis to another.
A few Mini-ITX designs even accommodate modest all-in-one (AIO) style liquid CPU coolers with a small (usually 120mm or 140mm) radiator, but these are the exception. You’ll want to examine the case maker’s spec for the tallest CPU cooler the chassis can support; many Mini-ITX models do not have the vertical clearance for tower-style coolers. Knowing this measure will ensure that sure your cooler will sit comfortably clear of the case’s opposite side, or not interfere with other components. (Especially in Mini-ITX cases, you can have situations where the power supply or other components overhang the CPU cooler’s mounting area and limit the possible cooler height, and this may not be apparent from the outside.)
Likewise, pay attention to the maximum length, width, and (potentially) vertical height (full-height versus half-height) that the case allows for video cards. Depending on the card you have, or plan to get, that sizing may be a deal-maker or deal-breaker. Some of the smallest cases don’t support a video card at all, and if you intend to rely on your CPU’s integrated graphics, this can be a great space saver. (Know, though, that some chips, including many of AMD’s mainstream Ryzen CPUs, do not have an integrated graphics processor, and that your motherboard will need to have an appropriate video output.)
Then there’s the power supply unit, or PSU. Power-supply support is also not universal in the Mini-ITX form factor. Compact small-form-factor power supplies (dubbed SFX, and offered by major majors such as Corsair and SilverStone) are purpose-built for Mini-ITX cases, but not every Mini-ITX case accepts one. Some cases do squeeze in full ATX12V PSUs, which are larger-bodied. (The mounting face of an ATX PSU measures 5.9 by 3.4 inches, versus the 4.9 by 2.5 inches of an SFX one.) Some cases will instead have room to mount a standard ATX power supply, while a handful of models can use either type, with the smaller SFX PSU installation handled via an alternative adapter bracket or other hunk of hardware.
You may also see support in a given case for a variant of the SFX form factor, the SFX-L. This is an offshoot, a slightly larger version of an SFX power supply with a longer body. (An ordinary SFX PSU measures 3.9 inches long, versus 5.5 inches for SFX-L.) The extra body size on an SFX-L supply allows for more and larger components and cooling hardware inside, in turn allowing for higher wattages. Don’t assume, however, that you can cram an SFX-L power supply into a case that only supports SFX PSUs. Look for that specific support.
To save space, an SFF power supply may seem like the best option for one of these systems, but they often cost more on a wattage basis than standard ATX PSUs and have lower power limits. (Current models top out at 850 watts, though that is enough for any reasonable and even most over-ambitious Mini-ITX PC builds.) ATX PSUs are the exact opposite, and using one of these instead will often make it possible to add more power-hungry components like a high-end GPU. Whether your Mini-ITX case can house and cool that extra hardware is another matter.
Another factor in a Mini-ITX case is its PSU cabling. The cramped confines of a Mini-ITX case means it is best to opt for a modular or semi-modular PSU design. These kinds of PSUs allow you to plug in just the power-cable “leads” you will use and leave the rest back in the box. Excess unused cable is the enemy in a Mini-ITX build—it blocks airflow and makes things look cluttered, especially in a case that might employ just the two main motherboard power feeds. (If you use onboard M.2 SSDs and no video card, those may be the only interior power cables you need!) A fixed-cabling PSU can saddle you with a giant knot of power leads you have no place to put.
Following from that, airflow is often an issue for Mini-ITX cases, due to their reduced size. Components and cables stuffed into a smaller space can more readily block air from passing through the case with ease, and heat tends to build up more, as a result. These cases can also be an exercise in patience to work inside of, due to the care required in routing cables and installing components in a logical order given the space constraints. (That’s another point in favor of using a modular PSU in any Mini-ITX case.) But again, like almost everything else with Mini-ITX cases, this all varies greatly from one case to another.
The Five Main Mini-ITX Case Types
At this point, the wide range of differences that can exist among a pool of Mini-ITX cases may seem daunting. You are probably starting to wonder how this can even be a single form factor at all. A form factor implies that it should be standardized, but in the case of Mini-ITX PC chassis, it’s mostly the motherboard size and shape that keeps this family a family.
In short, that means a Mini-ITX case can be just about anything—and they are. We’ve jokingly called Mini-ITX the least-standardized standard in PC building. That’s because these cases come in myriad designs on the outside, and you never quite know what to expect until you start to work on one on the inside.
To make looking over Mini-ITX cases more manageable, we’ve opted to organize them into five rough design types. Not all Mini-ITX cases will fit into one, but most do, and this scheme gives you a solid idea of the options out there.
Style 1: The Horizontal/VCR Style (Think Xbox One, Kids)
This flat design is what PC builders in years past often associated with home theater PC (HTPC) cases. Originally, most Mini-ITX cases used this design, but now it’s mainly used, where you see it at all, by OEMs. Still, a few models target end users, like the SilverStone Raven RVZ01-E, but as time has gone on, this design has fallen out of favor since most can’t host a full-size graphics card, and half-height graphics cards are a poor backwater for anyone needing graphics power.
These cases tend to be among the most compact, with some designed to support a monitor sitting on top. They also tend to be easier than most to build in, as opening one large side of the enclosure grants easy access to all of the internal hardware.
The downside? They also have the most hardware restrictions. Most mandate low-profile coolers, half-height add-on cards (if any cards at all), and SFX (or even smaller proprietary) power supplies. This makes them a poor fit for gamers but an excellent choice for a moderate or light-duty work PC (or an HTPC) that relies on processor integrated graphics.
Examples: In Win B1In Win B1, SilverStone Raven RVZ01-ESilverStone Raven RVZ01-E
Style 2: The Pillar Style
This second style of Mini-ITX case stands out for having the smallest footprints; most of the gear inside is mounted vertically. Pillar cases are designed to stand up straight, obelisk-style, and not lie down. The internal layout changes considerably, and in some of these, you can fit a full-height graphics card on end.
The internal layout varies from model to model. These cases also tend to be the most restrictive in terms of parts-installation order, and some use unusual special hardware such as riser cables to make big video cards fit, or passthrough cables to position a power supply in an unusual spot. SFX PSUs tend to be the norm in these tightly packed cases.
Examples: Phanteks Evolv Shift XPhanteks Evolv Shift X, SilverStone Lucid LD03SilverStone Lucid LD03
Style 3: The Shoebox Style
Now, what if you were to lay your pillar down? This third style uses a design that more closely matches a long, thin box.
These cases aren’t very high and may look squarish from the front, but are long front to back. Like the pillars, the main idea here is to fit a full-length video card.
Example: Cougar QBX Ultra,Cougar QBX Ultra, SilverStone Sugo 14SilverStone Sugo 14
Style 4: The Tiny-Tower Style
At first, you could easily mistake one of these cases for a larger MicroATX chassis. These are in fact smaller, however, and can’t hold a MicroATX board. This design isn’t as space-saving as most others, but it also means more room inside for hardware. The building process may be easier, too, given the extra interior.
For example, Fractal Design’s curvy Era ITX can hold ATX PSUs and standard-height graphics cards. It also has options for adding small AIO liquid coolers. And the Phanteks referenced below is essentially a scaled-down little tower.
Examples: Fractal Design Era ITXFractal Design Era ITX, Phanteks Eclipse P200A DRGBPhanteks Eclipse P200A DRGB
Style 5: The Cube (or Near-Cube) Style
This final style of Mini-ITX case may not be a perfect cube, but that’s the rough shape.
The blocky design doesn’t conserve much footprint versus a standard MicroATX case, but the height is low and the case luggable. These models are prized more for their unusual look and ease of building than sheer space-saving convenience.
Example: Cooler Master MasterCase H100Cooler Master MasterCase H100
So, Which Mini-ITX Case Should I Buy?
The easy answer: It comes down to the components you intend to install. For some shoppers, the look of the case tops everything, and that is fine. Just make sure to factor in some practical considerations, especially if you already own some of the parts.
The biggest one is whether you will (or will ever) install a video card. The very smallest Mini-ITX cases support no video card and assume your CPU’s integrated graphics will handle video output and acceleration. That factor will eliminate (or recommend) a whole swath of cases.
The second should be the number and kind of drives you intend to install. Most Mini-ITX cases support at least two 2.5- or 3.5-inch SATA drives, but factor in room for what you have. This won’t matter if you go all-in on motherboard-mounted M.2 drives, but cramped Mini-ITX boards have room for just one or two of those.
Third is power-supply compatibility. If you are bringing a PSU you already own to the build, make sure it matches the type (ATX, SFX, or SFX-L) that the case supports, and that it isn’t longer than the maximum rated length. While on the subject of measurements, make sure your CPU cooler and GPU will fit, as well; case makers supply those maximum heights and lengths.
And so, onward to our picks. The selection below isn’t a wholly comprehensive survey of every Mini-ITX case on the market, but we’ve reviewed a fair number and present the best we’ve seen for the last few years. We’ll add new ones as they pass through PC Labs.