If you get either the x800 or 6800GT, you'll be able to play anything just fine. Why some people say one of those cards is way better then the other i dont understand....theyre very close, each has small differences over the other. The x800 might be a bit better, but it costs a bit more.
Athlon 64 3500+ / Asus A8N-SLI Deluxe
1gb Corsair DC Twin-X (512x2) Pc3200 LL
2x Asus EN6600GT w/76.10 Forceware (It Helps)
Sony DVD RW DRU-710A / Toshiba 16x DVD-ROM
Thermaltake Shark Aluminum Case w/Asus 4 in 1 Cool Ice CPU Fan
Sound Blaster Audigy2 ZS
3DMark 2003 ~ 14682