Overview
AMD Black border/The Game is not 100% fullscreen, fix that worked for me.
The fix that worked for me
Was to Enable GPU scaling in the CCC
Not 100% sure what the problem is,
seems to be related to, AMD + HDMI + DX11
but this is my first game i had a Black border problem, so really i got no idea.
I hope this will be helpful to others, as web searches couldn’t find a simple solution.