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A few months ago I bought myself a new computer. Since then the monitor have been occasionally flashing black for a second or so, and I've been looking for - and failing to find - a solution. Will appreciate any help here.

Problem Description

The entire monitor turns black, lasting for about a second, then resumes display as normal. The computer itself continues running as usual. It looks very much how it looks when changing screen resolution. The frequency in which it occurs depends on whether there's anything moving on the monitor or if it's a static screen - flashing is less frequent when the screen is static, but still occurs.

The frequency have slowly increased over the last few months - at the beginning it was every few minutes and only under load (watching videos / playing video games), now it's closer to every second. This suggests a hardware issue, but read below.

Sometimes after the black screen, it won't return to normal, instead turning completely corrupt. In these cases even quitting the application doesn't help, but physically disconnecting and reconnecting the monitor fixes the problem.

In addition, the computer sometimes gets a BSOD, blaming a driver issue for the crash. This suggests a software issue, read more below.

System Information

NVidia GeForce 660 Ti
Core i7
Windoes 7/8 (see below)

What I've tried

  • Using a different monitor - does not solve the problem
  • Connecting the monitor via VGA instead of DVI - solves the problem
  • Connecting the monitor via HDMI instead of DVI - does not solve the problem
  • Using a different version of Windows - does not solve the problem
    • Tried clean installations of Windows 7, Windows 8 and Windows Server 2012
  • Using Linux instead of Windows - solves the problem
  • Using different NVidia driver versions - does not solve the problem
    • Also tried not installing any driver and letting Windows Update do its thing, didn't help
  • Playing with the monitor settings does not solve the problem
    • Tried changing refresh rate to 59, changing color depth to 16 bit instead of 32, lowering resolution
  • The presence or absence of other monitors does not solve the problem
  • Upgrading to a power supply with more wattage does not solve the problem

Both the working workarounds above are suboptimal to me - I prefer Windows over Linux and using analog connection leads to fuzzy image with my 1680x1050 resolution. Plus, I only have one analog-capable connection in my graphics card, while I would ideally want a 3-monitor setup.

What I Think is Causing the Problem

The fact that using Linux instead of Windows solved the problem makes me think that the most reasonable culprit is a faulty Windows driver. But how? Many others have a similar setup and it works for them...

What Does the Internet Say?

The symptom - screen momentarily flashing black - seems to be common enough:

But unfortunately so are non-Q&A forum sites where every cry for help is followed by multiple "yes, I have this problem too" or "have you tried updating to the latest drivers?". In any case I've tried following suggestions I've found, to no avail.


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No one can tell you with 100% certainty, but my top two guesses are the video card driver and the power supply. Since you're using such a new OS it would not surprise me at all to hear of driver bugs. Check the Nvidia forums for other users with similar problems, and also see if there is a newer beta driver available that you can test with.

If the issue lies with the power supply, either yours is not up to the task, or it's failing/faulty. What power supply are you using? I suggest buying or borrowing a quality power supply rated above what you need and testing to see if you still encounter this problem.

Other possibilities are: Hardware problem with the video card, or bios bug in the video card. If you can easily exchange the video card it would be worth a try. If not, updating its bios is also worth a try, though that is really a last resort long shot.

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A friend of mine had the same problem on his new computer. It ran perfectly using OpenSuSE and the nVidia proprietary Xorg driver, but did not work in either 7 or XP (he almost immediately downgraded to XP due to other software constraints - that was back in early 2012 and some all-important software was not (yet?) 7-compliant).

However, the only way to get the monitor behave with Windows was to splice two cables and go analog (and "fuzzy"), otherwise the monitor would "click" every minute or so (apparently depending on temperature), temporarily blanking the screen. We both immediately recognized this as the "changing resolution, please wait..." behaviour. No driver update solved the problem.

After an evening of head-scratching, rebooting and taking notes, we finally noticed that the monitor resolution was not reported the same everywhere; Linux consistently insisted that it was slightly less than 72 Hz (I think it was 71.98), while Windows diagnostics said 72 Hz. The other resolutions were slightly off as well. We reasoned that if some widget in the system was running at 71.98 and another was treating it as 72, maybe one of them would notice the discrepancy once it had became large enough, and that might well have happened every minute. The fact that it happened more often when running hot could be attributed to thermal drift. And then some emergency resync would take place, and that could have explained the blanking.

We started voodooing with nTune utility, and soon started trying "registry frequency" hacks. We also fiddled with the NVTweak utility.

In the end we found a utility by CleverTec, along with instructions on how to tweak the registry and cram the calculated values down into the Windows driver's throat.

So the good news is that the problem is software, is in the driver, and can be fixed.

The bad news is that I couldn't for the life of me come out with a precise HOWTO, since in the end we were pretty much moving at random, after having arrived at our wits' ends. I can't even guarantee that it was DTD alone that fixed things (I am quite confident, but not completely): maybe it only worked because of the previous work on nTune/NVTweak.

Also, be aware that tweaking frequencies can wreck both card and monitor. It never happened to me using X (where there's the same warning), and when I botch things usually the monitor clicks and displays "Frequency out of range", nothing more. But be careful all the same.

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Could you explain a bit more what you mean by "frequencies"? Are these update frequencies, as opposed to monitor refresh rate, or are these the same? Also I see some utilities and specifications mentioned horizontal and vertical frequencies separately... – Oak Apr 6 '13 at 10:22
Sorry, yes. Monitor refresh rates. I've only worked on that on Linux, unfortunatel. The mismatch was in the vertical sync, and what we actually did was to copy the Linux X modeline (which we knew was working) and paste into the DTD calculator with the usual trial and error voodoo. Here you find a (Linux-oriented) explanation: . – lserni Apr 6 '13 at 11:25
I think I have a similar problem, occurring when I boot the PC. Only thing that worked for now is switching the cable monitors (I have a Radeon HD 7800 that can manage 2+ monitors), but it is the first time I try this and may be is not THE solution. I'll let you know. – Andrea Antonangeli Jan 22 '14 at 8:45
If you get that at boot only, it could also be the video initialization, which just might be configurable from the BIOS setup. Look for something like "Display Order" or "Primary display" or "VGA Device Priority". – lserni Jan 22 '14 at 20:56
I'll have a look to it, since I have changed 2 video boards having exactly the same issue. BTW, for the moment the problem did not reappear from when I switched the cables as I told previously. Thx for your comment – Andrea Antonangeli Jan 23 '14 at 15:21

It's a bit of a long shot, but try to find any errors in the Event Viewer. I've had a problem with my nVidia graphics card (driver crashed when used heavily), and I had to update both the driver and the bios. If that doesn't help, well, you should turn the screen manufacturer for warranty (you said it's brand new).

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up vote 0 down vote accepted

I ended up replacing the video card and it solved the issue, I guess it was faulty in some way.

To whoever is reading this and is disappointed this ended up being the solution: sorry :-( hope you still have warranty!

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protected by bwDraco May 16 '15 at 5:06

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