I would check power supply on that also. Insufficient power output after warmup?
I wrote a new kickstart disk again, verified disk.
Power supply? Maybe, not sure.
Tried again with new kickstart. It is a good 10 seconds of solid access and reading, then just when it stops and seems that the insert Workbench disk prompt should appear, signal to monitor stops and blank.
As crappy as the case was taken care of on this, the motherboard and capacitors look brand new. Even the shielding was spotless. I tried reseating and chips etc, but still nothing.