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#51
Mechanical drives and flying heads.... when any diag finds and fixes bad sectors, the drive is failing. The coating on the discs might be scratched and that leads to more head crashes (bad sectors).
The perfomance of the drive degrades as the heads seek a place to read or write the data making multiple attempts to read.
I've had drives in service for a while after moving bad sectors. Did I trust them - nope. I knew it was only a matter of time before the performance or reliability made the drive more trouble than it was worth - chkdsk continually moved the bad sectors. I replaced the drive(s) when I could afford it.
But that was on my machine having a few years of experience with HD.
Since this isn't your machine and you have the replacement HD, I'd leave the original HD out of the equation. I wouldn't think about using the original HD as a secondary, because of possible future problems. You've been though enough stress on this project. :)
Glad you made it through all of this Greg. The next one will be easier