For years I had this problem with this monitor and AMD GPUs. WIth Nvidia it works, apparently Nvidia made a fix in their driver at some point.
The screen goes blury and there is no way to correct it. I found another person having the same problem
wrong screen size displayed
The only solution I found so far is to use a modified driver inf with edid override. It is just annoying that I have to disable driver signing and install this every time I reinstall windows. Can AMD fix this for good?