Does the extra 256MB of on-board memory make a difference for today's cards playing today's games? I'd think that once you get up there in the resolutions, & layer-on the AA & AF, the extra memory will likely come in handy. The TweakTown guys test out an X1950GT to see exactly what the differences are.

"We saw that the cut back to 320MB on the GeForce 8800GTS had quite the impact on performance and it often mentioned that 512MB can be handy on the right card as long as it had the GPU power to back it up."