I have extreme flickering of the screen (brightness flicker) when Freesync is in setting "Ultimate" when playing games. This is happening since a couple of versions of drivers. If I remember correctly the last working version was 18.6.1.
For sure the flickering is happening with 18.11.1 and 18.9.3 and only when the Ultimate mode is enabled.
Happening in World of Warcraft and Battlefield 1 / 5
It was not happening with any driver version before 18.6.1. In fact I tried 18.8.1 and 18.9.3 (and if I remember correctly 18.7.1) and installed 18.6.1 again which solved the problem. Now I have to use 18.11.1 because of Battlefield 5 and I am stuck with that problem.
I have a Vega 64 Liquid Cooled Edition and a Samsung 34CF791 connected via HDMI 2.0.
Since the problem disappears when installing an older driver version I am sure it is a problem with the new drivers and I am asking to investigate and fix the problem. I found other people reporting the same problem in other forums.
If you need more information, please don't hesitate to ask.