Since a recent upgrade from W8 to W8.1 I have a delicate issue with my monitors. I'm currently running a tipple-monitor setup where one is connected via DVI, one via HDMI and the last via Displayport-HDMI adapter. When I start the computer I can use all of them perfectly fine, but if they go into sleep-mode the third one (Displayport) won't wake up. Windows still detects it and acts if it's still there, but no video signal goes through. If I reboot the computer it still doesn't work - it must be fully powered off and booted from cold. I have tried the latest stable as well as beta drivers, but it doesn't seem to make a difference.
OS: Windows 8.1 Pro 64-bit build 9600
Mobo: MSI Z77A-GD65
Gpu: Gigabyte HD 6850
Drivers: Tried 14.4 and 14.6 beta
Monitors: 3x Samsung SyncMaster S24B370