This just started a couple of days ago- in the morning after my Imac has been asleep for a few hours, I will try to wake it by pressing the keyboard or mouse and nothing happens- powerswitch is unresponsive, I eventually have to unplug and replug to start it up. During the day it will sleep and awake normally, it just seems to happen after long periods of time. The only thing I can think of is recently there i installed an Itunes update, could this screw things up? I have a (pre intel) IMAC running OSX 10.3.9 -1.6ghz and 512MB