This is a small home server I built with my father, a nice little project. At first it ran on Linux Mint 17.1 with Kodi when it was in the living room, but I now have wired Ethernet in my bedroom so it's been relocated to under my desk and now runs a minimal Debian installation. It's totally headless, controlled via SSH from other computer in the house. It's used for file sharing, backups and media streaming with UMS.
Initially my father paid for the case and power supply, I bought the CPU (A4-6300), cooler (CM GeminII M4) and motherboard, the 2TB drive and SSD boot drive are old parts from my gaming PC and I got the first 4 GB of RAM for very cheap from friends, so it wasn't too expensive at first. I later added a cheap network card to bridge my single wired Ethernet connection to my gaming rig.
I almost finished a big upgrade on the side of a major overhaul of my gaming build. I added a Noctua NH-U12S and replaced the noisy case fans with two Noctua NF-S12B redux-1200. I also added a spare 8GB of RAM from my gaming rig, bringing it to a total of 12GB. The dual-core APU was good enough for what it currently does, but I decided to replace it with a quad-core Athlon to make transcoding with UMS smoother and host a Minecraft server for my friends. I made a small mistake there however: I had planned to get the X4 845 but saw the 860K on sale and got that instead... Turns out that it requires dedicated graphics to even boot, so I had to run to the local computer shop and get an old Asus GeForce 210 with a passive heatsink. The last part of the upgrade is a semi-passive 860W Seasonic Platinum PSU from my gaming PC, it will be added as soon as I get new cables (I tried to sleeve the old ones myself and it's not really pretty, I don't really want them in my server...)
The one thing I wasn't really satisfied with is the case. I wanted to get a Fractal Design Define Mini, but forum advice and some reviews suggested that Nanoxia was just as good and less expensive so I decided to give it a try. While build quality is okay, it's still not as good as the Fractal cases I've seen, and the stock fans were causing a lot of vibration, especially at the lowest settings. So it was either a "brrrrr" or a "hummmmm" noise that are both equally audible and could make it impossible for me to fall asleep if I wasn't very tired. Thankfully the new Noctua cooler and case fans solved this, and the PSU from my gaming PC will make the server completely inaudible, but it would have been from the start with the right case.
Other than all that I'll eventually need some more HDDs, movies and FLAC music sure take a lot of space. HGST/Hitachi has some very nice and relatively cheap entreprise drives that I'm looking at.
A good budget quad-core CPU for gaming or general use. Not the most energy-efficient or powerful, but very cheap for what it does. Required a dedicated graphics card.
Incredibly silent, big enough to cool effectively and allow overclocking but small enough to fit in smaller cases and not interfere with you RAM or motherboard heatsink. The build quality is outstanding, both for the cooler and fans. You get used to the color scheme very quick, it looks a lot better IRL than in photos.
Best Micro-ATX A88X motherboard out there, great value. 8 SATA connectors make it ideal for a file server.
Kingston KVR, the most generic RAM ever, typically bought by the hundred by OEMs. Works reliably with no frills, as expected from Kingston.
Heard a lot of horror stories about OCZ, but mine is over 5 years old and still works well. Wouldn't recommend anyways, OCZ when bankrupt for a reason and there are better, cheaper and larger SSDs available now.
Takes a while to spin up when you need to access files, but very silent when in use. Better used as an archiving/backup drive, large capacity at a very low price. This is true for newer WD Green models as well.
Lower build quality than competitors (Fractal Design), stock fans vibrate a lot.
Good low-end unit, runs cool and quiet.
Wired Network Adapter
Does what it's supposed to, and probably spies on you internet traffic since it's Intel.
You don't hear it at all and it still manages to move a decent amount of air. Build quality is as great as other Noctua products, but the package includes fewer accessories. At this price I can't really complain.