Do you hear the problem drive (Quantum?) spin up at all?
and after it spins up do you hear a kind of pop (This pop
is the latch releasing the heads on to the platter).
If you don't hear the drive spin up or the latch release,
the drive controller might be talking to the drive, waiting
for it to report ready, but never getting an answer.
If the drive is not spinning up it might have a bad field.
When the power is on try rotating the drive sharply along
the horizontal plane of the platter assembly, this might
move the motor enough to start it. If it starts don't let
it spin down 'till you get what you want off it.
This is how I saved the data off my old Seagate ST1480,
when one of the fields on the motor went bad. This was
about 3 weeks ago, and that drive was in my original
A3000D. I believe I got that drive in 93 or 94.
I was really suprised when it died, those 1480's
were extreamly reliable.
I used to work in the clean rooms assembling drives here
in Okc, 'till they moved everthing south of the border.
Wildstar1063