Ok so I just converted to the mac world and bought a new iMac a few months ago. I am not sure if my computer is supposed to do this or if I have a problem. I already had to take it to apple to replace the hard drive thanks to filevault but thats a whole other story. Anyway, here's the issue... when I get home from work I sit down at my computer. The screen is black. Cool! Screen must have dimmed. Should just move the mouse or hit a key and it should come on right? Nope. Nothing happens. The screen will not come on. So I'm thinking that maybe it automatically shut down after an automatic update or something. I hold the power button and then I hear the computer power down! WTF?! I release the button and push it again for it to power up. Everything works fine again. Can anyone tell me what is going on? Thanks!