I turned turning it off and playing Napoleon Total War yesterday and at 1920 by 1080 I don't think it's noticeable, even on the 40" screen you have to look closely at the edges of things to notice the slightly non-smooth edges. I think the more screen res increases the less AA will have any use. I've only looked at that on NTW I don't know if it's more noticeable of first person shooters, etc.