Yes, most of the benches I've seen show that you really only benefit from the 640 at resolutions of 1600x1200 or greater. There are a few exceptions like Quake 4 on Ultra Quality; performance is considerably better with the 640, but the 320 still has a more than decent framerate. The real question is, will DX10 games want the 640? So for the short term you'd be fine with the 320, but if DX10 games want the extra mem, you might want to upgrade in a year. From what I hear the 8900's might be out by then so it would be an even better upgrade...