THis is the same problem someone had on Aug 29. I was in the Apple store and a Service pack for word for mac started so I let it go and then it said it had to restart, although I don't think the service pack had fully installed. I closed it and took it home. A pale blue screen came up when I turned it on and nothing happened. Then it told me to do mac boot, which I did and nothing happened. Now when I turn it on the fan is really loud, and the screen stays black. I put in the install disk but can't see it since the screen stays black and can't eject it. I have tried all the suggestions in the manual.