>>2)  What would cause the PC to not boot every time you turn the power
>>switch on?  All of the lights come on, the hard drive spins up, but the
>>monitor never flashes the video bios message.  A quick reboot usually
>>brings it right on or turn the power off, waiting a couple of seconds
>>and then flipping it back on.

I just had this problem on a 486  The symptoms were exactly as you describe
and lasted for months ...I swapped power supply , ribbon cables...took the
whole PC apart and put it back together but the problem persisted  with
increasing frequency until the PC just would not post. The culprit was a
dying controller.  A GSI model 18 add in that had been used to supply LBA
support.  When it finally died it was easy to find....pulled it out and
everything went back to normal.

Mark