Okay, so, basically.... My Mac is set to sleep after about 30 minutes of inactivity. I've had it for two years, and it seems to have not had any problems with the sleep function in the past... Anywho, I left my computer to go to bed, and when I came back to it this morning, something weird happened... It LOOKED like it was in sleep mode, but I could not wake it, no matter what I did, and the fans were roaring rather loud. I had to completely shut down and boot again. I'm afraid it might happen again tonight, so I want to nip this problem in the bud before then. Help me out.