Interesting hard disk experience.
A disk (apparently) went really bad - the system would hang
during POST if it was plugged in. So, I got a new disk, got
it formatted and restored from backup, and about the time I
finished that process, it developed the same symptoms :-).
Figuring it couldn't possibly really be bad so quick, I dug out
a new sata cable and plugged it into a different sata connector
on the motherboard, and Presto! The data I just restored
was back, and the hangs went away.
Just for good measure, I reformatted and restored again,
and so far it is still working perfectly well.
Now I feel like I need to plug the original disk back in
to the new cable and connector and see if it is still
there after all.
If the onboard controller is going south, maybe I should
get an add-on sata card and use it instead? (Or maybe it
is time to use this as an excuse to get a new motherboard
and faster CPU :-).