This is hardware and therefore a touch off-topic, but anyway. . .

This beast appears to have no SCSI termination power.  Therefore you 
need something like a Seagate drive on the internal end in order to 
power the terminators, if any, on the motherboard.  Is there a jumper 
option on the motherboard to control this?

I'm extrapolating a bit from the configuration of the drive that the 
machine came with and the fact that I can't substitute a Quantum from 
another machine and have it work.  Any other explanation for why I 
can't move the primary drive to the end of the chain and take that 
Seagate out?  The Seagate was configured to supply termination power 
both to the bus and to the on-board terminators.

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h.b.hotz@jpl.nasa.gov, or hbhotz@oxy.edu