Powerbook G4 hardrive fault/white screen


Hi, a month ago the usual ticking & whirring noises of my powerbook were interrupted by some really unhealthy straining noises that sounded like my computer was eating itself from the inside. I got a spinning colour wheel and could not access the dock, force quit or the apple menu, could only shut down.

When I tried to reboot it went straight to a white screen, and there was a persistent whirr-click noise, like the harddrive was repeatedly trying and failing to get going. When you boot up holding down alt, you get the blue screen with the arrow buttons but no disk logo to select.

Target disk mode doesn't work, if you do alt-cmd-r-p or whatever it repeats the chime noise as many times as you like but then proceeds to the same white screen. It did awake from this coma and work again for a while but now it's died again (in the exact same way, preceded by same noises).

Any ideas?