Ah, another 6800 vs. X800.... The 6800s are more future proof than the X800s, as they feature PS3.0. The X800XT P.E. is a pretty good card, but doesn't match the 6800 Ultra or even the 6800GT in many cases, especially in Doom 3. The X800 Pro has only 12 pipes instead of 16 and therefore has crippled performance.