Homebuilt Linux

I was wondering if anyone out there had any experience building computers to specifically work with linux. Im lookingto build this computer as a main server to host hdtv related media (dvr, web video, music) and at the same time I would love to use it to setup a local intranet so that I can use it as a freelance development box. Im thinking I can get away with getting just onboard video for right now, but Im trying to find a good motherboard that has dvi/hdmi out and still supported in linux. any suggestions?

This computer is not going to be used for games, but I wouldnt mind the ability to play a couple older games that require 3d acceleration.

Ive decided already to go with ubuntu - just the reglular distro - Im not that big a fan of mythubuntu. Does anyone have any better suggestions for os?

I recommend you get nVidia chipset, the GeForce 8200/8300 chipset for AMD or GeForce 9300/9400 for Intel-platform. They have good working drivers and are powerful enough to play a game with, actually i run games on that chipset under Ubuntu linux. Don't expect miracles, but it works. DVI and HDMI should also be working, however HDCP (the copy protection) is most likely not, but you don't need that part, right?

Phenom II + GeForce 8200/8300 mobo + 4GB DDR2 memory + WD Green HDD would be my choice in your case i think.