Thank you for the replies.
I sort of cheated. I used the restore discs, put Windows 7 on the machine, and then used a home-made DVD created using Microsoft's "Media Creation Tool", and upgraded it AGAIN to Windows 10.
Uh... It worked. Microsoft didn't question it, it shows as activated, and I'm happy. Even had to do it a second time when the old hard drive failed (which I suspected would happen, considering the motherboard had gone dead, and hard drives have circuitry too.) Once again, no problems.
I have no idea why they let me install Windows 10 on a machine with a new mobo, since usually an installation is tied to the board, but I'm not going to complain. The computer works and all's well.
Thanks again for your input.
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AQ 31
Your Aspie score: 100 of 200 / Your neurotypical (non-autistic) score: 101 of 200
You seem to have both Aspie and neurotypical traits
What would these results mean? Been told here I must be a "half pint".