Monitor goes to sleep when screen has lot of black.

Hello,

First of all, I can't remember when and how this started, but definitely after upgrading from Windows 8.1 to Windows 10 Pro.

So, my screen (Acer LCD, connected to GTX 560 with 1 meter DVI cable) started going black (power light on, background light completely off) when I watched a video that had lot of dark on it.Happens in some games as well where the cut scenes change.

I tested it by full screening a plain black image and the screen went to sleep, mouse cursor dissapeared.
Moving the mouse does not wake up the screen, only when i press Win key to bring up some color to the screen. (the task bar seems to be enough to wake the screen.)

I have checked all the power settings and turned off all the sleep settings, 'Turn off display after' is set to 'Never'
'Multimedia settings' are set to ' Prevent idling' and 'Optimize video quality'

What is happening?

Edit: Nvidia driver version is 355.60

I would start with some troubleshooting. First I would boot into safe mode and see if it does it. If doesn't, you have narrowed down the problem somewhat. If it does, then boot into a completely different operating system (such as a Live Linux disc) and see if it still does it. Another thing you could try is a different monitor if you have one, and/or a different video card if you have one.

So, my screen (Acer LCD, connected to GTX 560 with 1 meter DVI cable) started going black (power light on, background light completely off) when I watched a video that had lot of dark on it.

Check DVI cable, reconnect it. If it still appears. Try switch DVI to VGA. You graphic card don't have VGA connector, so try lend from friend DVI/VGA adapter.
If problem still appears try to use another DVI cable to be sure it's not cable problem.
Try to use your monitor with other PC/Laptop if it works. If it's fine it's not monitor fault.
Try to change cable, if problem still the same, it's not cable fault nether monitor.
Try to reinstall graphic card with NVIDIA/AMD Uninstaller from here
If problem still appears reply. It may be graphic card issue.

Just wanted to echo that I've been having this exact same issue since upgrading from Windows 7 Pro to Windows 10 Pro. My monitor is an ASUS, connected to NVidia GTX 680 by a 3-foot DVI cable. I haven't found a solution yet, if you find one on another site would appreciate an update here.

My quick debugging
Issue occurs with other DVI cables
Issue does not occur when monitor is connected to another computer
Have not tried a DVI-VGA switch
Nvidia drivers are up to date, I keep them current with the GeForce experience tool

It really appears to be an OS issue to me, though I don't see where in Win 10 to configure anything related

Thanks for all the replies.

I tried HDMI connection but the level of black was so bad the monitor didn't go to sleep.
I messed with the monitor menu settings and noticed I had ASUS ASCR (Asus Smart Contrast Ratio) set ON and turning that OFF, fixed my monitor sleep issue on DVI connection (black levels still being as before)

Thanks for all the replies.

I tried HDMI connection but the level of black was so bad the monitor didn't go to sleep.
I messed with the monitor menu settings and noticed I had ASUS ASCR (Asus Smart Contrast Ratio) set ON and turning that OFF, fixed my monitor sleep issue on DVI connection (black levels still being as before)

That fixed it for me as well, thanks!