Hi folks Got a problem with my late 2009 iMac (spec in my sig). It recently developed the flickering display issue that was a known fault with this model. Sent it back to my local authorised Apple dealer who fitted a new display under AppleCare warranty. Got it back a few days later this last Thursday. OK, so the new display is fine bright, colours look great, no flickering. But the graphics are awful. As in, when doing something graphically intensive, they stutter as if the machine is overheating or something. I was halfway through Dirt 2 when the machine went in it used to play great for an hour or more easily. Now the game is totally unplayable even in the first race. So I thought maybe the new display was brighter or something and taxing the graphics more. So I turned the brightness down to half, installed iStat pro to monitor temperatures and installed SMC Fan Control to force the fans to speed up and keep the temperatures down. Temperatures dont seem too bad now, but the graphics are just as bad. Im guessing Ill have to haul my machine all the way back to the Apple store again, but to save me the hassle, I wondered if anyone had any ideas, or had experienced something similar themselves? Thanks guys.