Okay, About 30 minutes ago my iMac 27" screen stopped working, I tried various things to get it back and ended up ringing apple, I have to take it into the shop on Monday, ALTHOUGH... I have an external screen pluuged into the thunderbolt, when I load the mac up it displays a grey secondary screen, I can't see the primary which is where the log on screen is, therefore I can't log in.. I need to be able to log in to be able to switch the secondary screen to primary!! Does anyone know away of choosing your login without seeing the screen.. is it possible to activate the tabbing option? Please help! Can't believe this has happened to the iMac.. Its only a month old!