I would go with 2 monitors and have one for browsing. But if you have three monitors, that means that you are basically running the game three times. Metro 2033, which I think is probably the hardest game to run, gets 48 fps 680 sli in 1920x1200 resolution at highest settings. So that is really the only game you would need to turn down settings for. BF3 would get about 50 I'd guess, it gets 130 with one monitor. But I think it might be best to get just 2 monitors, and if you do get two, I would recommend getting a cheaper one for your second monitor.