Just bought a new monitor (Lenovo Y27q-20) and it looks like all the games that support DX12 don't use freesync unless I force DX11:
WoW
Grid (2019)
Red Dead Redemption 2 (freesync works in Vulkan)
Anno 1800
I know this is the case because the difference is very obvious when it comes to how smooth things are and because the built-in monitor HZ counter stays steady at whatever the game's FPS is when DX11 is enabled. When playing with DX12, the HZ counter is all over the place.
However, there are two games that don't seem to work well with freesync even in DX11—DiRT Rally 2 and apparently Warcraft III: Reforged, but those are the only exceptions so far.
So, what gives? What's up with freesync not working for me in DX12? Could the monitor be faulty (I imagine freesync wouldn't work at all if it was), or it's because of something else?
GPU: Sapphire Nitro+ 5700XT (latest drivers)
CPU: i7 4790k
Mobo: Sabertooth Z97 Mark I
RAM: 16 GB 2400 MHz
PSU: 750W
OS: Win 10 Pro (up to date)
The monitor is connected via display port.
VSync on or off/fullscreen or borderless fullscreen makes no difference regarding this.