I'd run an Asus X38 board instead of an Intel. Most Intel board wont let you overclock and a lot of guys run 3GHz and over on a Q6600 quad. I'd make sure that Intel board allows clocking before I bought it. I run 64bit Vista Ultimate in my main gaming rig. XP and DX9 are yesterdays news in hardcore gaming. Play Crysis, Lost Planet, Bioshock in DX10 and you'll see why. You'd want to up the ram to 4GBs so that would cost you more. The ATI 3870X2 is now the fastest video card out, 7% faster than the Ultra and $250 less at $449. ATI card also runs DX10.1 while Nvidia's sticking with only DX10 until DX11 comes out. DX10.1 is nicer than DX10 but a mute point if you're gonna run XP and DX9. The Q6600 quad is, in my opinion, the hottest little cpu out right now considering its performance for its price however the 2.66 Ghz Intel Q9400 is due out within the next month. With its 1333FSB and 45nm artitecture some reviewers say its over 25% faster than the Q6600 and is a perfect mate for an X38 board. About 90-100 more than the Q6600 but a bargain considering the Q6700 is $540. I use WD Raptors in my Raids but those 2 80GB drives will work nice. The way your rig is designed you should have no problem maxing out any game except for Crysis, especially running XP and only DX9 which requires less from the video card. I've run Aspire(now Apevia) PSUs in gaming rigs and, with their open window and glowing cables they look really sweet, especially with UV tubes.