Can anyone help?!?!? My Powerbook G4 550mhz makes an unhealthy ticking noise and freezes on startup, I have tried everything - Hardware test, booting from software/restore disks, removing ram, removing battery, I also hooked it up to another mac and copied the HD just in case and the Powerbook actually booted up but the ticking and freeze came back after 5 mins!!! I have sensitive info on the HD so tried to firewire to another mac to erase - but now it isnt recognized! So sending it to apple is out of the question. Anyone experienced this or have any ideas?!?!? Desperate!