Comment # 25 on bug 1183676 from Stefan Dirsch

Ok. Verified that vrr_capable is enabled in "xrandr --props" output when set
with monitor.

Result. Samsung curved monitor has FreeSync Off/Standard/Ultimate. With Off you
always get 60Hz, with Standard/Ultimate things get switched to 100 Hz - fixed.
No matter what I change the fps rate to with VRRTest. So things are just not
working as they are supposed to.

I also tried the amdgpu kernel driver option freesync_video. Indeed it was
disabled by default. Didn't change anything in behaviour. 

I also tried without amdgpu X driver, just using modeset, but of course with
freesync_video option set. Same result.

So indeed I can reproduce this issue on my RDNA2 card - RX 6400.