I guess I need to mention my experience of building my own small ITX computer. My first computer since the family computer I had built with my father in 1997.
As I mentioned earlier, I’ve been following this market for a while so I was already well geeked out in the subject. I figured out the hardware that made sense for my use. I intend on doing some CAD, simulation/rendering, odd photo/video project and some light gaming from time to time. I figured I’d go with a very cheap enclosure as I plan on running my computer in a prototype case quite soon 
I used the website PC part picker to decide on the parts, find deal and ensure compatibility. It’s truly a great resource. Ensuring parts would fit was extremely simple for me as I purposely chose small parts so they would fit into what ever case I decide to build.
This is the case I ended up with. It’s fairly small, though quite a boring box. I had the thing running in an afternoon. And most of that time was spent tracking a memory stick that hadn’t clipped in properly. Contrarily to most stories I read online that small PCs were very hard to build and even not recommended to first time builders everything went quite smoothly. Of course being a mechanical engineer that’s been tinkering with electronics for a while doesn’t really put me in the novice section.
I did run into an issue with my power supply. Even though it was touted as being very quite for a small PSU, it even has a silent mode if the PC isn’t under load, my unit was extremely loud. Loud enough to hear the fan ticking from the next room while the computer was idle. I ended up exchanging the power supply but the replacement was just as loud. So reading online, it seems like most small form factor PSU have issues with noise. Early standards were too small (SFX) and had tiny whinny fans. More recent slightly larger standards (SFX-L like I have) still have some kinks to iron out.
I ended up fashioning my own solution.
I strapped a fan right on the PSU so it states in it’s silent operation due to the continuous air flow. Typically, the fan in a power supply is used as an exhaust though I use mine as an intake and just blow air directly onto my CPU cooler.
It actually made my whole computer much quiter. And actually got me wondering if it would be possible to replace virtually all the fans in a PC with a simple fan right after the power supply. Use a single fan the draw fresh air through the PSU, the directly down onto a heatsink to cool the CPU and finally have the air cool most of the motherboard before naturally exiting the case. This could be a very efficient design versus having a fan for the PSU, one for the CPU and finally one or several just for air flow in the case.
So what I gathered from this little adventure is that.
- Small power supplies are very hit and miss and possible a barrier to small form factors.
- Well integrating with a part selection tool like PCpartpicker is a must and should get promoted by the manufacturers.
- Manufacturers should provide well produced instructional video. The few companies I’ve found that do it seem to be well appreciated for it.
Next up, inspiration then I can finally start sketching. Dragging my feet did allow me to figure out a lot of stuff though!