I’m running a msi gtx 1050ti with amd ryzen 5 1600 cpu and 2 gskill ram 8 go and I get regular frame dips in easy to run games such as fortnite or rocket league typically running at 100 and it will drop below 50
I know ryzen has been released for a year, but it could be that those games are not optimized for the new ryzen architecture yet.
You could try disabling SMT to see if that helps, but a legit hard fix might have to come out of the game developers.