I'm running vista 64 bit and I have a newer 8800GT 512 (G92) and my old 8800GTS 320 with 4 monitors, one being 1920x1080, and I have virtually no problems in major cities. Occasionally an addon messes up and i get ~25 fps, but most of the time the minimum I get is 30-40FPS on my main, with all the eye candy turned up. When I used to single box, without addons i'd get around 120+FPS and honestly, 40 and 120 look about the same.