At this point I'd normally provide some troubleshooting steps, but it looks as if you have performed most of them already.
Then next thing to try would be a clean installation of Windows, so you'll need to backup your data first.
Fully Update Windows (this will take several restarts)
Install our latest drivers
Install your other software include MS Office.
Following that order should resolve the issue.
I don't know how much fiddling you want to do before going ahead with Matt's suggestion but..
I have the same motherboard and cpu and win10x64 and it's working fine. Right now the difference is I don't have a discreet GPU installed. So if you're up to it, pull out the 290x and on restart go into bios setup and make sure Settings/advanced/integrated Graphics config is set to Init graphics adapter - IGD and Init graphics devices as Auto. Now if you get to desktop and radeon settings doesn't load try the DDU route once more.
If everything is good then put the 290x back in and change from IGD to PEG save it and restart. Don't forget to change the vid cable back to the 290x.
If that works then try the latest driver update again.