I have also tried your other suggestion, lowering the resolution to 1920x1080, and you're right - then the problem is gone. So I'll try with a different display cable (I'm now using the one that came with the monitor).
I have also tried your other suggestion, lowering the resolution to 1920x1080, and you're right - then the problem is gone. So I'll try with a different display cable (I'm now using the one that came with the monitor).