Sounds like there's something wrong with the OS. If you're using the same builds and setting as before and after, that's the most likely culprit.
Check for any driver updates for anything (Intel Driver Update online, AMD drivers, optional Windows updates).
Also if you just copied the files from your old Windows to an external drive and then back onto the new Windows, try clearing the cache for Dolphin.
Check for any driver updates for anything (Intel Driver Update online, AMD drivers, optional Windows updates).
Also if you just copied the files from your old Windows to an external drive and then back onto the new Windows, try clearing the cache for Dolphin.