What's the problem? It happens when the screen is at 120hz, 144hz. At 60hz it's ok. I'm using the displayport and a brand new cable. The monitor is a Samsung CJG5 27"
32" WQHD Gaming Curved Monitor CJG5 with 144 Hz Refresh Rate | Samsung Support South Africa
Amazon.com: SAMSUNG 27" Odyssey G55A QHD 165Hz 1ms FreeSync Curved Gaming Monitor with HDR 10, Futuristic Design for Any Desktop (LS27AG550ENXZA) : Electronics
Samsung's CJG5 gaming monitor is great | VentureBeat | VentureBeat