I came back to my Powerbook to find the screen black and a strange buzzing coming from it It wouldn't boot, so I tried the install CD and ran disk utility. The internal HD is not listed. - I guess the HD is dead? - Any suggestions what to try now? - Any recommendations for an new drive? Can I fit a 100Gb? - Please give specs of what drive I need. - Are there instructions anywhere of how to do it? Thanks for any help. Edit: I turned it off for a while and unplugged it. It now boots, but I would like to know about replacement drives anyway. Many Thanks.