Little bit of a PSA.
If you are running MSI afterburner + Riva tuner ( primarily Riva tuner running ) and updated to the last few AMD driver updates since I think May, can't recall then Davinchi resolve would crash.
For some strange reason this crash would occur since the last few updates from AMD but the older drivers from March or April would work but with Resolve update 19, if you used an older driver sometimes it wouldn't detect a GPU at all.
Recently just removed MSI afterburner and Riva Tuner ( luckily don't need it anymore ) and this will fix the problem but honestly, this isn't the first time I've had issues with MSI afterburner + Riva Tuner in general.
But @AMDVik, I also took the liberty if trying the Pro drivers for the 7800XT (the latest one), which actually install ( and actually runs a little smoother then the most upto date gaming driver ) but this also does not detect any GPU in Davinchi resolve free version and can't figure out why.
so far when it has come to the drivers, not had issues in game for some time but Resolve recently has been a right stickler of problems.