Thanks for the info mate.
I followed the procedure but the issue remains. 50fps on 13.1 catalyst, 120fps on 12.8 catalyst.
- I uninstalled using the official cleanup tool. Followed by a reboot.
- I removed remaining entry's using driversweeper also followed by a reboot.
- I installed the 13.1 catalyst package + reboot.
I also stumbled upon a thread where people have the exact same issue: