I currently have a 3 monitor setup (5760x1200) using a single GTX 780 Ti OC'd to 1200Mhz... I Play all my games at medium to ultra settings ( depending on game) MMO's i get about 50+ FPS on highest settings, BF4 gave me ~45-50 FPS on high settings, CS: GO i get ~200-250 fps on max settings (although i limit it to 120 fps). The highest amount of vram i've seen my card use was 2.8 gb... I know some games out now can use 3gb at 1080p (watch dogs) but i think that is because it is poorly optimized. Personally i find 3 gb of ram to be plenty and a single gtx 780 ti provides me with playable frame rates at pretty high settings in most games. If you are worried about future games needing more vram you might want to consider going with the GTX...