Just wondering whether or not this is normal but my 2011 27" iMac sometimes gets incredibly hot on the back top right and left corners. When I say hot I mean almost too hot to touch. This only happens sometimes and when it does happen the fans are running normally, not maxed out or anything. After restarting and shutting down it can still get really hot but other times its cool and not a problem at all. Could this be caused by something im doing, a program im using? I dont have a great deal of software installed but I was thinking perhaps watching videos on youtube could be causing it? That being said it happens after restarting, shutting down etc so was wondering whether anyone here had any suggestions or could put my mind at rest. Thanks.