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
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  • Simozene - Wednesday, May 25, 2011 - link

    I am currently in the market for a small NAS box and was debating on whether to buy a 2 drive model or build my own FreeNAS system. I think it would be useful if you guys did a similar guide for building a low power FreeNAS system that supports 2 to 4 hard drives as it becomes very difficult to figure out what parts to select in such a system.
  • chrone - Wednesday, May 25, 2011 - link

    yeah need a guide too, especially when using ubuntu as the NAS OS.
  • obsidian009 - Wednesday, May 25, 2011 - link

    Save yourself some time and headaches -- pickup an inexpensive Synology NAS like a DS211j, a couple hard drives and be done with it! I agonized over the details of building my own NAS for months -- ended up doing the Synology and have never looked back!
  • dcollins - Thursday, May 26, 2011 - link

    Just want to second the Synology NAS recommendation. I used two of their boxes at work and absolutely love them. Excellent web GUI and 90% of a full linux system if you ssh to the box. If you want to be able to install new software, try to get one of their Intel Atom based boxes because there is more software available in the repository. For me, that meant being able to install python for scripting.

    Great boxes with excellent online documentation through their wiki.
  • Simozene - Thursday, May 26, 2011 - link

    Thanks for the suggestion. The DS211j seems to be exactly what I need for a small home NAS. I doubt I could build a small and power efficient system for under $200 anyways so it is probably not worth the effort to go with FreeNAS. I would still like to see a NAS building guide on Anandtech though; as another reader pointed out a FreeNAS box that supports more than 2 hard drive is often a fraction of the price of the retail counterpart.
  • StormyParis - Wednesday, May 25, 2011 - link

    I'd go with an element Q case, replacing the PSU if silence is paramount. These fit up to 3x3.5" HDDs (on in the 5.25" slot), then any Atom MB, preferably a very simple one without ION, single core is enough if you do neither RAID nor encryption. I just built one such, except it doubles as an HTPC, so I went the Windows route, with an AMD E-350 whch is both overkill and a pain (FreeNAS ?) for a pure NAS. I got one internal 3TB drive for it, and an external one for backups. I'd rather start off with a single large drive and be able to add another one later on.
  • iahawkeye - Wednesday, May 25, 2011 - link

    I completely agree and am in the same boat. I've been planning on building a small NAS box based on FreeNAS or some flavor of Linux for a while now, but I have little to no experience in selecting parts for such a PC. I'm also completely new to Linux and have been wanting to branch out, so a walk through or guide on this topic would be awesome.
  • 'nar - Wednesday, May 25, 2011 - link

    I went with a HP MediaSmart, mostly because I couldn't find a box that took 4 hard drives and was so small and easy to swap drives with, FreeNAS not-with-standing. I'd love a guide as well, but that is predicated on there being any suitable devices that actually exist.

    Mediasmart has been discontinued now, and I really need a simple workgroup backup/storage device.
  • sullrosh - Wednesday, May 25, 2011 - link
  • kepstin - Thursday, May 26, 2011 - link

    I have one of those; It's a nice case, but the included fans are quite noisy. I keep mine in the basement, so it's not a real issue for me...

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