you've already got ddr2 and pcie, so off the bat, you'd only need cpu and motherboard. you can upgrade bits and pieces as you go.

lot of p35 boards real cheap

cheapest at the moment looks to be http://www.mwave.com/mwave/viewspec....9&RSKU=BA23929
$90 with a $20 rebate to make it $70. I actually just got this deal myself, but the board is still in the fedex box since I just moved houses and haven't had time to play with it yet.