Defining Small Form Factor

What, exactly, is a small form factor (SFF) system? Like many computing solutions, there’s no industry standard definition everyone follows. Typically, SFF systems accommodate either a mini-ITX or micro-ATX motherboard, a desktop-class CPU, desktop (or in some cases laptop) RAM, 2.5” or 3.5” hard drives, slim or standard optical drives, flex ATX (slim) or standard ATX power supplies, and sometimes (but not always) a discrete video card. SFF systems usually are not the way to go if you need room for housing more than a couple hard drives; likewise, they generally aren’t optimal for very high-end (and therefore hotter) CPUs like Intel’s and AMD’s hex-core chips, or high-end GPU configurations including SLI/CrossFire setups. Most ITX SFF systems only offer one expansion slot, and that one is usually low profile, though the micro-ATX sized systems frequently have room to accommodate more potent configurations. Thus, depending on your definition of SFF and system size, you can build everything from tiny and silent boxes up to very powerful and capable systems.

SFF systems offer a number of advantages compared to larger traditional desktops. First and perhaps foremost, they are of course small in terms of physical dimensions. This is an especially important consideration where real estate is at a premium, like in a dorm room, smaller apartment, or work cubicle. Even if you’re not particularly limited for space, a smaller computer frees up space for things you’d rather look at—like a larger monitor! Some SFF cases are as tiny as a shoebox. Others are a bit larger, but none of them approach the dimensions of a full-size or even mid-size ATX tower. This makes SFF systems ideal for HTPC use, placed alongside other smaller (relative to a traditional desktop chassis) home theater components like receivers.

Second, because they are small, they are also less massive. SFF systems are light enough for all but the puniest computer nerd to carry with one arm—or less flippantly, more convenient for elderly or disabled computer users to manage. The combination of small size and light weight makes them far more portable than traditional desktop computers. That leads us to the third point: you can pack a lot more computing power into a SFF system than a similarly priced laptop. If you don’t need the portability of a notebook and you need more power on a budget, SFF systems are reasonable alternatives to laptops—especially if you have peripherals ready to go wherever you’ll be taking your SFF. For example, SFF systems make great LAN party gaming rigs, and I carried an SFF between a research lab and my apartment for a semester twice a week when I couldn’t afford a sufficiently powerful laptop.

SFF systems do have a number of limitations as well. As noted above, you simply can’t fit a lot of components in a tiny space. Perhaps the most important considerations in assembling a SFF system are heat and noise. Cramming a bunch of heat-generating parts in a small space makes for a toasty chassis. Given the small dimensions of a SFF case, you’re often stuck with 80mm (or smaller) case fans, which typically move less air and generate more noise than 120mm (or larger) case fans—though many newer SFF cases (particularly mATX sized chassis) feature 120mm fans. The advent of small computer cases with improved airflow and larger fans has greatly mitigated the heat and noise concerns of their predecessors from even a few years ago. However, noise and temperature are still a concern for SFF systems. This point highlights the need for a well-managed interior—larger chassis are more forgiving of messy cabling, but SFF systems typically demand neat (i.e. time-consuming) cable management.

So with that out of the way, if you’re looking to go small and go home with your small system, let’s get to the builds. This month’s guide features two builds—one Intel-based, one AMD-based—for each of the following types of computers: basic, general purpose office type builds for the budget-conscious; HTPCs with an ear toward low noise; and gaming rigs with an eye toward graphics performance. We also discuss alternative components for some of the systems. As with our nettop guide, we are including six different cases—two for each of the builds. Unless otherwise noted, the “Intel” and “AMD” case choices are interchangeable, and the same goes for the storage and other components. Only the CPU, motherboard, and potentially memory (and IGP in situations where we’re using integrated graphics) differ, so when looking at the final price we will only compare AMD and Intel based on those differences.

Budget SFFs
Comments Locked


View All Comments

  • Gigantopithecus - Wednesday, May 25, 2011 - link

    I completely agree, which is why I clearly stated "AMD’s Zacate platform (discussed in our last guide) is far less powerful than an i3-2100T system, but keep in mind that it is sufficient for most HTPC tasks."

    That is, already covered.
  • MrTeal - Wednesday, May 25, 2011 - link

    As of yesterday Intel released the new Sandy Bridge Pentium chips, and Newegg has stock on at least the G620. The 620 might not be that appealing, but the G620T looks identical to the i3-2100T other than the 300MHz drop in CPU clock. For $50 less, it might be a pretty good downgrade.
  • beginner99 - Thursday, May 26, 2011 - link

    Yeah just saw them too. The G620T looks really nice for a NAS or HTPC. Extra CPU power compared to zacate can be useful in a NAS (RAID). Also Zacate MBs are pretty expensive where I live especially the ones with a usable amount of SATA ports (more than 4) meaning price wise a G620T won't cost much more.
    For a NAS the main problem is a decent case. This mean small but space for at least 4 hdds. Chenbro ES34169 looks cool but very expensive...
  • max40watt - Wednesday, May 25, 2011 - link

    I suppose this is more in line with the Nettop article, but I built a delightful mini itx AMD Fusion e-350 based desktop in an old NES console a little while back. I've been using it mostly for htpc use (netflix and hulu over boxee software controlled via an iphone) but it's also proven to be fine for light gaming.

    I was worried about the heat inside of the Nintendo, but so far it doesn't seem to be a problem.
  • Drag0nFire - Wednesday, May 25, 2011 - link
  • Avlor - Wednesday, May 25, 2011 - link

    Another great case for small form factor PCs in CoolerMaster Elite 100. It looks ok-ish, provides reasonable options for storage and will accommodate mATX boards despite being similar in size to that by Foxconn.
  • Aikouka - Wednesday, May 25, 2011 - link

    Zach, I recently rebuilt my server with a Core i3-2100t in an ASRock P67 Extreme6 motherboard. I actually used the stock heatsink/fan (HSF), which I normally don't do. I figured that it couldn't be too bad, right? I knew it'd probably be a little warmer. However, what I was very surprised about is how noisy that stock HSF is. I can literally hear my server from a room away, but my HTPC (Core i3 540) using a Thermaltake SlimX3 is fairly quiet (still audible within a few feet).

    To be fair... I'm not 100% certain that it's only the stock HSF's fault and not the motherboard doing a poor power management job. I told the motherboard to allow the CPU to go up to 50C, but it seems to never get that high, which makes me think it's not reducing the power properly.
  • Gigantopithecus - Wednesday, May 25, 2011 - link

    Bizarre! I wouldn't call the stock i3 HSF silent, but the one I have in my music box up in my loft is inaudible ~10ft away with music at lower volume settings. Something is up with either your particular HSF or your board's regulation of its juice. Also, remember to check basics like having the HSF plugged into the HSF header and not having the HSF plugged into the chassis fan header (with the case fan plugged into the HSF header). I've done that before. :p
  • Onus - Wednesday, May 25, 2011 - link

    I built a gamer in a PC-Q08R last year (slide show of build on YouTube under user "jtt283"). I also used a 550W Truepower New. The CPU is an i5-650, on an ECS H55H-I. Initially I used a HD4850, which exhausted its heat. I switched that for a GTX460, and noticed a definite (though not hazardous) increase in temps, that also increased CPU cooler noise but not intolerably. I would be perfectly willing to use an even more powerful GPU, but it would have to be another that exhausts its heat. The fact that it will mount more drives than the mobo has ports means I may very well repurpose this machine as a backup server for the other PCs in the house.
  • Bobsy - Wednesday, May 25, 2011 - link

    Hi, just wanted to say this is a great article. For people who do not work in the field (building computers all day long), it's a great starting point for more research if desired, or a great shortcut for someone who just wants to get the job done. Very professional and well written. Thanks.

Log in

Don't have an account? Sign up now