I have a Windows 8.1 PC with ATI graphics (78xx series) card with up to date drivers. It's driving an old Iiyama 22" 1920x1080 50Hz LCD panel over a new DVI cable. I have two HDD, a little SSD for the OS and a couple of big magnetic discs for storage.
When playing games, my I sometimes see artefacts before the game crashes. Sometimes Windows crashes too. It happens on DirectX (up to date and under 9, 10 and 11) and OpenGL (both pre-v2 version and later).
After ensuring vents were clear, heat was under control and cleaned contacts etc, I returned the graphics card to the people I bought it from (Scan), who ran it under load (3DMark benchmark) for 24 hours without a fault being found.
Drivers are up to date and the windows dump crash report (when it takes out Windows) says that an unknown hardware fault occurs.
The rest of the machine runs fine when under load - I run artificial intelligence algorithms (no GUI) on it that run the 3 of the 4 processors at 80% and 10 of the 12GB of RAM used for 2-3 days without a problem. During that time, there's also high disk access against the magnetic discs.
If the monitor goes into standby, it sometimes omits a high pitched buzz sound after a while. I've replaced cables and isolated power.
Is it possible that a fault in the monitor is causing the graphics card to crash?
The only test I can't easily do is borrow another monitor, because I would need to borrow it for a period of time.
Edit
A co-worker has suggested I try a VGA cable, which is not plug-and-play. It's a good idea, I'll try that tonight (if the GfX card has a VGA out) and report back. VGA cable made no difference.
Tried 3DMark (it was version 11) to reproduce the test that Scan computing did, and found that it was still crashing.
Tried the onboard adapter - not powerful enough to run the same games but showed that there wasn't a problem in OpenGL.
You might also want to make sure it's actually outputting 50 Hz, and not 60, though, again, that shouldn't cause this particular kind of crash
Tried that, definitely outputing 60Hz.