Good luck with the Ryzen and 8.1 it may or may not work. Are you doing a clean install or from an image, what about Windows authentication, does changing a CPU and I presume motherboard invalidate activation?
Just posted a post in hardware issues , MS is blocking updates on the older operating systems if they are running on the new gen of processors.
I have a retail version of 7 pro, and updated that to 8 pro, and in turn to 10, so my version of Windows 10 is retail, so I can activate it on any computer as long as it is deactivated on the other machine.
Not sure what I will do, i do no really want to do a clean install as the amount of plug ins I have for my video editing software is a pain to reinstall,, even if I have changed to using different software most of the time, I still need Vegas installed.
i could just try and boot up with the drive as it is on the new system, or make an image and use that.
I am using 10 at the moment, but to be honest, it annoys me, so I think I will go back to 8.
not sure when i am updating, I am thinking of doing it when my next week off work comes up, which i think is next month.
Desktop machine now powered by windows 8.1 pro 64bit, no dreaded metro, laptop by Linux