d'oh!
The only thing I even use my media center for is Frets on Fire, and if I can ever get the damned TV-out working on my 8800GTS I'll just play on from my main comp, so I figured why waste a perfectly good 160GB 7200.10 SATA300 hdd!?
Gonna move my OS to it and me games and let the slower 300GB hdd be the mass storage drive.