I am busy working on this iMac G3 Rev A Tray Load. It boots up fine and a picture comes up but as soon as it starts to boot into the OS, it goes black. Now this does not happen all the time, just most. I have tried it from a hard drive with 10.3.9, a CD with 8.5, 9.0.4, 10.2, and 10.3. The...