Thanks again for all the potentially useful replies.
I found an older SATA drive with a 1.5Gb/3Gb jumper -- that wouldn't 
work either.
And then, guess what?  I replaced the SATA cable, and now it all works 
perfectly.
Try not to think of it as time wasted, more as a lesson (re-)learnt.
In my defence, the cable must have been border-line: it was working very 
recently (i.e. this morning).
cheers
Chris
-- 
Chris Dennis                                  cgdennis@???
Fordingbridge, Hampshire, UK
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