I am thinking the following parts as a workstation, please comments. The budget is about 3-4K USD.
AMD 939S Opteron 180 Dual Core CPU DFI Lan Party UT SLI Expert DR Mainboard Mushkin XP 4x1 GB DDR 500 Memory Sticks PNY Quadro FX 1400 PCI-E Graphic Card 2x 74GB W.Digital 10K RPM Hard Disk (Raid 0) Silverstone Case and 500W Enermax Liberty Power Supply
even a single italy would give better bandwidth... perhaps on a NF pro 2200 board? that will also allow you to upgrade you memory later as well.
Latest workstation: Lian li PC-A05B, KN3-SLi, 4400 Brisbane, Freezer 64 Pro, 2 gigs Super-Talent T800UX2GC4, 36 raptor system drive, Caviar RE 320 storage drive, Hiper 580, Ati 1300 Pro, running Vista Home Premium 64-bit with Symantec 10.2.224