Small Form Factor Build Guide
The decision process that sets this type of computer building apart from standard builds in the OP is that a lot of component choices are based on the selected case. So rather than finding a case to fit the parts you've picked out, the case will determine parts compatibility. To further compound the issue, each motherboard may only work with a select number of heatsinks without causing interference or mounting issues.
What I am going to focus on here are the cases that have the ability to hold and power fully fledged gaming rigs that just happen to be smaller than their ATX counterparts.Cases that are aimed at extremely low power consumption, limited expansion, and minimal cooling have been omitted.
There are five cases that stand out as obvious choices for these builds right now. The CoolerMaster Elite 120, Silverstone FT03 Mini, BitFenix Prodigy, Lian Li PC-Q08R, and the Silverstone SG07/08. Each of these present different features and drawbacks.
CM Elite 120
The Coolermaster Elite 120 is an inexpensive case that is perfectly suited for a budget SFF build. There is enough room for most current videocards, but the airflow is anemic enough to where you don't want to cram in power hungry parts like a 7950 and an overclocked 2500K. One way of overcoming this airflow issue is by replacing the front fan with a fan that has a high pressure rating, like the Scythe Gentle Typhoon or Corsair SP. However, if high end parts are what you are looking to install, you will want to look elsewhere. Here's the proposed build for the Elite 120.
Silverstone FT03 Mini
While gorgeous, the FT03 probably has the most stringent requirements in terms of parts selected. For starters, if you want to overclock then a closed loop 120mm water cooler like the Corsair H40/60 is mandatory. There just isn’t enough room anywhere else in the case for a decent aftermarket cooler, and Silverstone actually designed the case with these units in mind.
The second is that since the parts are oriented 90 degrees, you have to be very careful when selecting a videocard. Cards with heatpipe designs do not perform as intended, so you will want to go with a reference video card. There are some non-reference coolers that will perform adequately, but you need to check specifically with the card in mind before purchasing. With all of that hot air dumping into the system, I’d still advise against it. Considering that AMD reference cards are still fairly loud towards the high end, if you want a computer that performs quietly, you will want to go with a 660Ti, 670, 680, 7850, or 7870.
The third consideration is that since airflow is fairly poor, you will want to replace the bottom fan with a pair of high pressure/CFM fans. Swiftech Helix, Scythe Gentle Typhoon AP-15, Noctua NF-F12, Noiseblocker Eloop 1300/1900 RPM are what you want to be looking at.
The final issue is that you are limited to SFX PSU’s only. Luckily, Silverstone makes two great ones, but you’re going to be limited to 450W. This is plenty for even a 680 and a 3770K. You will want to avoid NVIDIA’s high end Fermi cards (GTX 4xx, GTX 5xx) though.
BitFenix Prodigy
The BitFenix Prodigy, while not overly expensive at $80, has the honors of being the most capable in terms of powering high end components. The drawback to this capability is size. It's quite a bit larger than any of the cases listed here due to the large handles. Really, the only compatibility issues you will need to deal with are whether or not a specific heatsink interferes with the motherboard layout.
Because of size, allowance of all different sorts of coolers, this case is the most capable of performing silently. You can even watercool your entire system with a custom loop, as it is capable of holding both a 240mm radiator in the top and a 200mm radiator in the front.
Lian Li PC-Q08
The Q08 is another case that is best served by a closed loop 120mm cooler installed on the top exhaust. Other than that, you’re pretty much open on part selections.
Silverstone SG-07/08
These cases are pretty much identical other than the front fascia. Though the price is high, they both come with decent 600W PSU’s, so they’re not overly expensive in the scheme of things. The only limitation you will face with these is having a low profile heatsink. You will want to use the CoolerMaster Gemini II or Noctua NH-C12.
As always, please notify me if you notice any errors or if you have some useful information. Thanks!
-zfz.Michalius