Yes, that's true. But the game will be accessing the hard drive more often because a 256 meg card can't store as many textures as a 512 meg can. It will need to swap them more often, resulting in more stuttering when the new texture is being loaded from the hard drive. I also have an 8800GT and I certainly noticed alot more stuttering when using QTP3, even the Redimized version, than I did with just the stock textures. Not only did it happen more often, but the lag was longer when it occurred. Which is why I haven't bothered with the NMC textures. I'd rather have smoother performance than hi-test graphics. There was a thread here awhile back where someone posted a You Tube video which showed his game almost grinding to a halt at times due to stuttering, and he was looking for help trying to fix the problem. After he removed the NMC textures his game played smoothly again.
You are missing the point. The video chip in the laptop the OP is looking to get, the textures will be super low res from their vanilla medium-high state that the Vram is a moot point. His biggest bottleneck will be hard drive seeking. The game procedurally loads as you go, and as a result, needs to access the hard drive a LOT. With a 5400RPM, seek times will be low, causing the stutter. Vram issues at low settings is a NON-ISSUE. The laptop has effectively 2256MB of Ram. Yes, normal Ram is used as Vram. Once the Vram is filled, it will spill over to the system Ram.