I seem to be having to same problem.
My monitor just goes black, then no signal then into standby mode.I have to turn off my power supply to reboot. Ive tried updating all out of date drivers via SlimDrivers and i still get the issue.
Ive tried to deliberately cause it to happen but sometimes it will do it after a few mins then other times it can be a few hours, i can be in a major city or event, or i can be in the middle of nowhere leveling a lowbie alt
any help would be most appreciated