Windows machine suddenly turns of displays and stops responding

This seems to be happening at random times and I have not noticed any patterns in usage (I've had this happen while watching movies, playing games, and idling).

Both monitors will suddenly go black, complaining about having no connection (at the monitor level, as though the machine was suddenly turned off). The machine, however, appears to still be on. All fans are running and lights are still on. If any of the components are failing, there's no signs as to which.

The OS doesn't seem to have merely turned off the display, because sound stops too. Hard restarting the computer temporarily fixes the problem.

Both monitors are plugged into the same graphics card. I tried switching one to the motherboard and it worked, but it was at the bootloader screen, which seems to imply a hard crash.

Event viewer doesn't mention any crashes. From the most recent crash, there's no events between 0924 and 1600 (at which time I rebooted the machine). There's an event that says the previous system shutdown at 0924 was unexpected (there's no events for the exact time) and then there's the event for me having hard restarted the machine at 1600. There's an event from 1600 that says the computer has rebooted from a bugcheck (The bugcheck was: 0x00000116 (0xfffffa801290c010, 0xfffff880030cc67c, 0xffffffffc000009a, 0x0000000000000004)).

The computer is not running hot at this time. I've checked for loose cables. I figure it might be a component, but I'm not sure which to look at.

Components are:

• Windows 7 Home Premium (with all the latest updates)
• i7 2700K
• Kingwin 750W PSU
• ASRock Z68 Extreme3 motherboard
• GTX 560 Ti
• Adata 256GB SSD
• Samsung 1TB HDD
• 8 GB of G.SKILL Ripsaw RAM

Monitors are two separate brands (an Hannspree and an HP). I don't believe the problem lies with them, though. Their reponse is correct to the OS cutting out the display.

Of note is that my keyboard has backlights that turn off when the displays turn off. Some of the times when this problem occurs, the keyboard backlight will go out, showing that it recognizes the displays have been turned off (but one time it didn't do this).