I'm now using:
Device name: NVIDIA GeForce 9800 GT
Pixel shader: 3
Estimated VRAM: 1000 MB
Motion blur: Yes
Actually 512MB video RAM.
(I was temporarily using: Device name: NVIDIA GeForce 8500 GT , Pixel shader: 3, Estimated VRAM: 997 MB, Motion blur: Yes, It's actually 512MB.)
(Before that: Device name: NVIDIA GeForce 8800 GT, Pixel shader: 3, Estimated VRAM: 997 MB, Motion blur: Yes. Actually 512 MB.)