Question Second monitor turns off after one second.

Apr 18, 2019
Hey there,

after long years of being able to successfully troubleshoot most problems myself, I´ve hit a dead end with this one:

Recently my secondary monitor stopped working in a weird way:
After turning it on, it would show an image for about a second and then immediately turned black.
Turning it on and off again (yes...) made it come back and turn off after a second again. Before that happend I started to get some interference issues, with small vertical noise lines, that went away with a little jiggling on the cable, so my first guess was a broken cable

Here is my troubleshooting procedure so far:

  1. Switched cables from my good monitor to my bad monitor.
  2. Bought new cable.
  3. Updated Nvidia Driver.
  4. Booted in safe mode.
  5. Checked power settings.
After none of that worked, I got a cheap used replacement monitor and guess what...same problem.

So now I´m a bit stumped...Did I get that unlucky and the replacement has the exact same issue, which I have never encountered before?
Or is there still some stupid hidden setting I accidentally activated?
Or is it a cable problem? The main monitor has a DVI-D Dual Link cable, the replacement monitor uses a DVI-D Single Link cable (With which the old monitor used to work).
If I plug in the DVI-D Single Link cable into my primary monitor, I get a display error (noisy lines).
I also tried accessing the OSD of the monitor, but wether the DVI cable is plugged in or not, I can´t access the OSD Settings, since the display also turns black after a second.
Which makes it seem like its more likely a hardware issue (unless I don´t understand how monitors work and it won´t show OSD controls, when there is no signal coming in).
I´ve read something about broken Backlights, but those posts said there should be a faint image visible, when you light a strong light at the screen, which is not the case here.

I also get a short glimpse at an error message from the monitor before it turns off, saying something about "out of range", but like I said, booting in safe mode didn´t fix it and the settings are already at 60hz.

I can´t test the replacement monitor on a different computer for at least another week or so and I don´t wanna buy another one without ruling out other possible issues (software or hardware related), so any help would be appreciated.

My specs:

Nvidia Geforce 760 GTX
Windows 10
LG Flatron W2346T


Sep 18, 2013
What you should do is go back to the basics and have only ONE monitor plugged in and test it. If that checks out fine, then unplug that and plug in the other monitor and test that. What you're checking for is to make sure it's not the monitors being at fault. If both pass then it could be you're having incorrect native refresh rates that is acting up.
In other words, if one monitor's native refresh rate is 60 and the other anything other than 60 then it's not communicating properly. This could happen even if drivers are updated, or even from different manufacturers but still within the same specifications.
If you're using Nvidia, also use the Surround feature which will try to match both differing monitors the best it can so things such as out of range and/or other strange errors can be reduced. Good luck!
Apr 18, 2019
Thanks for the reply, but I already tested the monitors separately. The primary monitor works fine, the secondary doesn´t. I think I even tried booting with just the secondary monitor plugged in and I had the same problem, but I´ll try that one again. Would be very easy to test if the monitor is simply faulty, if the second monitor works on a different PC, but alas, I´m stuck here out of town in the middle of nowhere til next week....

I´m just confused because the image comes on for a second everytime I turn it on and off, thats why I still think its more likely to be software related.