As well as electronic failures, look for mechanical problems.
Can you hear it spin up to speed in time to be recognized?
Look for lost jumpers, bad connections, broken pins, components
that have been damaged by bumping against something.

Sometimes simply disconnecting and reconnecting the ribbon connector
(between the card and the disk proper) where it plugs into a socket
like a tiny version of an isa socket can "clean up" a bad connection.

Older versions soldered directly to the board can also crack near the joint.
You would need a delicate hand to resolder/repair such damage, but it can
be done.

When electronics fail, it is usually sudden and permanent.  The
intermittent problems are usually a bad connection, or worn parts such as
bearings.

Boyd Ramsay

[log in to unmask]

         PCBUILD maintains hundreds of useful files for download
                     visit our download web page at:
                     http://nospin.com/pc/files.html