Eugene,
   What happens if you just hook up the Hard Drive and not the DVD?
If it boots that way, there might be an issue with the DVD drive.
However, failing that test are your Hard drive and DVD drive connected
by different data cables on the motherboard?   One of the controllers
on the motherboard might be bad, though that is a guess.  If they are
connected separately, what happens when you connect the Hard Drive and
then the DVD drive along the same data cable where the DVD is showing
up?  If it boots, then you could have a data cable issue where the
hard drive was hooked up or a bad controller on the motherboard where
the hard drive was hooked up.  One controller works (DVD motherboard
connection) but the other (Hard Drive motherboard connection) does
not.

Derek Buchanan

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