following up a message from JIM HOLSONBACK to JEAN PARROT:

 JH> From this and your other posts to/from Matt, sounds like either 
 JH> the HDD has died, or perhaps the first IDE channel has died on the 
 JH> Mainboard.  I had that happen to me about a year ago on an Asus 
 JH> board with AMD k6-2.- HDD suddenly stopped working and wouldn't 
 JH> autodetect.  I moved it to the secondary channel and it 
 JH> autodetected just fine and I could access the drive. Turned out 
 JH> the first IDE channel had just up and died, for no apparent reason.

That's possible.  But what hit me when I read of this initially was the
same thing that hit me this time -- possibly a bad cable?  I'd try another
ribbon cable before anything else,  then if that doesn't work try the other
connector on the MB.

Also,  try swapping the _power_ cable to the drive for a different one. 
Sometimes those have been known to loosen up.

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