First what is it for?
Why not a P5K MB? and why 2 500GB HDD's?
why not a 1TB Samsung spinpoint F1 HD103UJ
and while I'm at it what about a Q6600 go stepping CPU? and a Radeon HD4780 Graphics card.
This sort of set up with your X-Fi soundcard would make a decent gaming rig, of course you now have to look at cooling, PSU and a case what did you have in mind for that?