Tested in cp2077.
I shouldn't have bothered in the first palce. somehow it makes things worse when I enable it with game running at 55-65fps vsr on. there's more lag, less fluidity, tearing-like artifacts, despite the panel reporting around 100hz in freesync mode.
it works well with native res at 80-90fps, but also produces some artifacts. not that bad, but I prefer 80 fps without it to "160" fps with it. the frames are doubled technically speaking (afterburner reading is wrong, but panel osd indicated around 2x hz value when it's enabled), but the increased latency makes it a bit less responsive overall, and there are motion artifacts on top of that.
will be testing in rdr2. if that's the same, I'm putting the 6800 right back on the shelf.