I have a PC built of a Gigabyte GA-Z77X-D3H motherboard (running latest BIOS F16) and GTX960 Rev. 1.1 GV-N960WF2OC-4GD graphics card. Before getting the graphics card, I had always used the on-board graphics, where the PC was solid as a rock. If I just connect a monitor via DVI to the graphics card, everything seems fine. If I connect monitors only via Display Port (2 x Dell U2515H) then if the PC goes to sleep, I cannot get it to reboot. I can reboot it explicitly, and that is ok, but if it goes to sleep it won't wake up. In fact it appears completely dead, so pressing the power button or keeping it on for 5 seconds has no effect.
I even tried changing my power supply since I feared it was a power issue, but I am confident I can eliminate that.
With a monitor connected to the graphics card by DVI I can send the PC to sleep as often as I want and it wakes up as expected.
The graphics card has the latest driver and the motherboard has the latest non-beta driver.
When the PC is powered up with the Display Port monitors, everything is perfect; it is just when it goes to sleep. I have disabled Hybrid Sleep already.
This is driving me crazy since the whole point was to move to a triple-head DisplayPort monitor configuration.
