Well I almost have my new build summed up, but can't make a definitive decision on graphics card. I would like to use an Nvidia card, and have two of them for SLI.
Here is the essentials of the build. Budget to add in graphics is between 600-800.
Antec Three Hundred Black Steel ATX Mid Tower Computer Case
Western Digital Caviar Black WD1502FAEX 1.5TB 7200 RPM SATA 6.0Gb/s 3.5" Internal Hard Drive -Bare Drive
GIGABYTE GA-990XA-UD3 AM3+ AMD 990X SATA 6Gb/s USB 3.0 ATX AMD Motherboard
CORSAIR Enthusiast Series CMPSU-850TX 850W ATX12V v2.2 / EPS12V v2.91 SLI Certified CrossFire Ready 80 PLUS Certified Active
G.SKILL Ripjaws Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model F3-12800CL9D-8GBRL
AMD Phenom II X6 1100T Black Edition Thuban 3.3GHz, 3.7GHz Turbo Socket AM3 125W Six-Core Desktop Processor HDE00ZFBGRBOX
ZALMAN CNPS9700 LED 110mm 2 Ball CPU Cooler
LG Black Super Multi SATA WH12LS30 LightScribe Support - OEM
Two of these would do ; EVGA 012-P3-1578-AR GeForce GTX 570 (Fermi) Classified 1280MB 320-bit GDDR5 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card. There is a rebate and that would make it $700 for the two. (Newegg)
This is also an interesting option you could check out at Newegg ; EVGA 02G-P3-1387-AR GeForce GTX 460 (Fermi) 2Win 2GB 512-bit GDDR5 PCI Express 2.0 x16 HDCP Ready Video Card. This would be $800 for the two.