That my 2008 iMac is one of the affected ones of the infamous 8800 GS card failures. After gaming today, the computer completely locked up. Tried several reboots, but the computer just freezes and the screen flickers a little. The odd thing is though, that the mouse pointer still works. I'm almost certain this is a gfx card issue because these model iMac's have been known to fail. The HDD was just replaced this year, so it can't be that. The GPU temperature is around 150F... Anyway, what do you think Apple will tell me? I bought this computer on December 25, 2009 so I still have one year and a half left on Applecare.