today i went to start up my powermac G4 and it didn't boot, so i zapped the pram and tried again...no dice. so took it out of my computer and put it in my B&W G3 and it did the same thing.thinking it need to be repaired I booted off of a CD, but it didn't even show up on the desktop!!! and when i went to run the disk setup software to see if it would so up there it wasn't even listed. I know that the HD works because I can feel it spinning up when I turn on either computer.......

I know its the HD because I have a separate Ubuntu HD and it booted off of that fine

Please help!!!!!!!!!!