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Ok, so I have a user who we've just deployed a machine for.

He can work for about 30 minutes, and then his screens just go blank. Like, nothing from the computer registers. No freezing, no blue screen, no anything. Nothing in the error log, no kernel dumps, nothing. Computer can be immediately restarted and has no problems - screens come up, Windows runs, everything is happy. For about a half hour.

I checked out his temperatures, they're like 30C, so it isn't that. I was thinking it might be a power supply, or video card issue.

Does anyone have any suggestions or insight about what can cause screens to go dark after 30 minutes? Note, the computer is still on when this happens.

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" I was thinking it might be a power supply, or video card issue." You need to verify these are not the issue. it sounds like the computer is shutting itself because of a hardware failure. – Ramhound Jul 11 '12 at 13:53
up vote 1 down vote accepted

Could be graphics card, monitor, or something else... start with the stuff that easy to verify and work backward:

I would start by swapping monitor and cables with another PC to rule that out (it's the easiest).

Then I'd swap the video card with another machine if available to see if the problem stays with the PC or follows the card.

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If the numlock key and the power button works when it's blanked out, it's probably a driver issue.

Various versions of nVidia's drivers are known to do this. Try a different version.

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I would start by booting with a memtest86 boot disk to rule out bad RAM or an operating system issue. Also, verify that Windows activation occurred successfully, and that there's no malware installed.

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