IMO, extra VRAM does not enhance graphics in general. What you see in the game's graphic settings is what you get. An HD6870 2GB can output the same graphics quality maxxed out in bf3 the same as its 1GB variant. An HD4850 512mb outputs the same IQ as it's 1GB variant in Elder Scrolls Oblivion. Now some games, has in game graphic settings which can only be enabled once you got sufficient vram. GTA IV and Max Payne 3 are some of the examples, but that's usually anti-aliasing related and just a portion of games out there which does not implement it. Now we all know what anti-aliasing does, and it's impact in relation to VRAM. The more the VRAM, the smoother the game is once you got AA maxxed out. I personally experienced it in Medal of Honor: Warfighter. On my HD6870 1GB, I can max out the game, with full AA but I get random stutters even if I'm hovering around 50-60fps. MSI Afterburner OSD reports vram usage around 900mb+. Turned off AA and switched to FXAA and I got smooth gameplay. The point is if the game utilizes more than 1GB like Crysis 3 max out then a user with say an HD7850 1GB can pretty expect the same quality as an HD7850 2GB user. The only difference is that the HD7850 user will experience stutters. Now as for mid-end cards, useless and additional VRAM. You may be able to enable the vram related settings on Max Payne 3 with a GT 640 4GB but performance would suck cause performance would still be the same as a GT 640 with less vram.