I have the same problem with the Samsung CHG90, before about driver version 18.6 and earlier it was only in menus on games like BF1, BFV - non problematic. Now with newer drivers it flickers everywhere, no matter what FPS - ingame at any FPS in different amounts.
Tested with GTAV, CS GO, BF1, BFV, The Division 2 - all the same.
I tried all the workarounds mentioned in possibly all threads around there on reddit and here. New Club3d High quality DP cable, driver tests, resets, DDU, CRU, different configurations, weird other suggestions over the last week.
It really narrows it down to only the driver as the problem.
Monitor: Samsung 49" CHG90 QLED Gaming Monitor - freesync
Graphics Cards: 2 x Asus RX Vega 64 - crossfire
Resolution = 3840 x 1080
Processor: Ryzen Threadripper 1950X
RAM: 48 GB, CL 14
