What games does this happen in?
What you tried benchmarking your system using the free Timespy benchmark (a part of 3DMark)?
3DMark is for gamers, overclockers and system builders who want to get more out of their hardware. With its wide range of benchmark tests, 3DMark has everything you need to test your PC's performance.
store.steampowered.com
Use "download demo" to get the free version.
Can you link to a score?
My instinct would be to do a clean installation of Windows. i.e. create a bootable installation media:
Boot from the media. Do a custom/advanced installation, delete all partitions on the OS drive, and then install Windows.
This wipes out what's on the drive, so back up any key data first / take an image of the drive with free software like Macrium Reflect.
Allow Windows to handle all driver installations, except for the GPU driver which you may want to source yourself directly from the AMD website.
Do not install any software except for a mainstream game client e.g. Steam, and a game to test performance.
This would (largely) rule out other software or an OS/configuration/driver causing an issue.