Alright, tons of good news!
TL;DR Its done, runs amazing and quiet, and is already deployed and happily serving up files to my AppleTV!
I managed to get the Geforce 210 working; I needed PCIRootUID=0 for the card to work, in addition to the usual GE=Yes. The noise from the card doubled the overall output; but the build was barely audible in the first place, so I'm overall happy. Once I get more funds, I'll either go with a passively cooled card, or just go for broke and throw in an i3 with an HD4000.
The CPU still thinks its an i7, but theres no adverse effect from this: Speedstep still works perfectly, and the whole build in a tiny little HTPC case with a single fan only runs 30C. No clue if sleep works; since its a sever, I want it always on. Same goes for USB3, I have some portable USB3 drives, but since I put a nice fat drive inside, I don't need external storage (yet.)
For anyone else curious about trying this with the Celeron's IGPU, it works but takes some fiddling and you have no GPU acceleration and the resolution is stuck at 1024x768. For a server this would most likely have worked, but I was seeing a lot of warning messages hit console.log and didn't want to have to worry about any loss or performance.
On the software side, its running OS X Mountain Lion with Apple's Server.app to provide consolidated management for file sharing and remote management, and also let it function as a Time Machine backup location. I played with Server's App Store caching, but for a home environment, it just made more overhead; a machine on the network goes to download a Mac or IOS App Store app or update, then the server catches this request, downloads the update, then transparently serves it to the client.
I've got all the voodoo set up to where TVShows.app will check for new episodes of shows I subscribe to and download them in Transmission. From there, Hazel runs some folder actiony goodness and if the file is an mkv (the usually are), runs it through iFlicks to remux it to m4v and add metadata. From there, iFlicks imports it into iTunes, trashes the original, and sends a growl notification. I've got growl hooked up to the iOS app Prowl, so the notification from the server hits my iPhone. From there, I can tap the notification to automatically launch Apple's Remote iOS app, which auto connects to my AppleTV, letting me start playing quickly.
Here's a picture of her, already set up in the TV stand, wired up to my gigabit switch, and sitting beside my giant (in comparison) main hack:
https://www.dropbox.com/s/tikkbftx8jxl0q9/Photo May 18, 20 09 02.jpg
