Well, there is an easy way to test it...
Make your screen window 1024x768 and check whether the problem still exist (I bet it will not).
Install a SW lke GPU-Z or NV monitor (I forgot the name
) and watch how the VRAM usage is reaching the maximum memory installed in your card. I bet your problems start when your available VRAM is reaching its full capacity.
Subsequently, you know how to fix it...
Personally I say, 2-3 generations of GPU cards we need to wait before we can see real improvement happening....
~S~