that's not the difference
venice has lower voltage (i think), has SSE3 instructions, and some other stuff that makes it better than the winchester
1.) you chose the TT 480W 20pin psu, that won't work; get an OCZ modstream 450W
2.) bump that DFI lanparty from SLI down to normal
3.) if you bump those ram down to twinmos ram (very good ram at only $94.35 for a gig on newegg), then you might have enough money to bump up your gfx card from the 6600gt to the 6800gt