First of all, i would like to say that this isnt one of those ahh the back of my iMac is hot...I know all about the aluminum being a heatsink. I actually have real temps. During the day, browsing the internet in safari my hard drive temp goes up to 52C and stays there until the iMac sleeps for a while. It idles around 48C which is high for idle...when i play a game it goes up to 56C at which time the fan ramps up to 1300rpm or 1500rpm then it stays there for the next hour even if i quit the game...i know that temperatures over 50C for a long time are not good for a hard drive...and temperatures over 55C for a long time is pushing my luck...I keep the A/C on 68F and i get these temps...my brother turned off my A/C and played starcraft for 5 hours without ever looking at the temps...who knows how hot the iMac or the room temp got, with the A/C off ive noticed this room can hit 80F...the iMac shut down on him and i think it was because of the heat...the machine im on is a 2.7GHz quad core i5 27" 2011 model with nothing upgraded...it has a 1tb western digital drive in it...S.M.A.R.T. status is verified right now...but when i do a disc permissions check, i get this this message, "Warning: SUID file "System/Library/CoreServices/RemoteManagement/ARDAgent.app/Contents/MacOS/ARDAgent" has been modified and will not be repaired. ". Does that mean that my drive is failing? or is it something not to be worried about...also, to my fellow iMac owners, what are your HD temps, do you think i should be worried about this? Other than the hard drive all temps seem to be fine...i've included a screen shot of iStat during a stress test of my iMac. Thanks in advance!