I had the problem running an Intel 8700K on a Z390 board. Changing to X570 and a 3900X did not help. I had the issues with both my old Vega56 and the newer 5700XT
Here is the details:
Clean windows install... clean driver... I don't do driver cleaner, I nuked my windows 10 installation every time I want to update my driver. That's how desperate I was. So don't tell me to clean the driver, there's no other driver before.
CORSAIR AX1600i just in case the old PSU is the problem. 1600W is enough.
Turning off all free sync and enhanced sync.
Running 3 monitors: 2x Acer XF270HUA 2K 144hz and a BenQ SW271 4K 60hz.
Instant black screen when I load the heavy games such as Total war 3 kingdoms or the witcher 3.
Random black screen after 20 mins or so in lighter title like Rocket League or League of Legends.
Unplugging 2 monitors, leaving only 1 Acer monitor, still black screen with less frequency.
Using BenQ 4K only at 60hz seems to produce the least black screen but I'm not gonna game on that 60hz panel.