I'm using a custom built Ryzen 7 1700 machine with an Asus RX560-2G OC Edition video card. It's driving 2 LG 27UD58-B 4k monitors, one by DisplayPort and 1 by HDMI. Been working great up until the Windows Update that was released for the Spectre and Meltdown bugs. Windows auto updated and I came home to a black screen on all monitors that was not resolved until I unplugged one of them. A driver reinstall later and I got both working somewhat....
Now the displays will work great UNTIL the machine times out and puts them to sleep. Windows keeps running and when I wake the computer the monitors will turn on to a black screen and I think Windows is still running as there is HD activity and it responds to pings. But no USB activity and no wake up. Sometimes the HDMI monitor will show the desktop while the DisplayPort monitor will be blank. Other times both will be blank. Hitting the reset button makes the system reboot. If I run one monitor things seem fine.
I've tried clean installs of:
- Adrenalin 17.12.1
- Adrenalin 17.12.2
- Reinstalling the AMD chipset drivers
- DDU and reinstalling the Adrenalin drivers
- Uninstalling the Windows update
Same deal. About the only thing that seems to work is a single display - be that DisplayPort or HDMI.