Windows 10: My graphics cards aren't supporting multiple monitors all of a sudden.

I have a system with a Geforce GTX 970 graphics card and a Geforce GTX 760 card, which each run 2 monitors, for a total of 4. 8 core AMD, with 32gb ram. Win10.
A few days ago a plug-in for Adobe After Effects needed me to upgrade my graphics card drivers via a prompt, and I allowed it to proceed. Usually I DL direct from Nvidia. After a restart, several Adobe products (up to date through CC) began to crash on start-up.
Upon checking, it seems the driver selected for me was not the current Nvidia 372.90. I uploaded to that, which yielded no better results. The whole system was performing fine, except the three graphics intensive Adobe apps all continued to crash on start-up. Several days of troubleshooting, with clean uninstalls, re-installs (of both Adobe and Nvidia) got me nowhere. Then yesterday, after rolling back the Nvidia drivers (with no luck) I upgraded back to the 372.90. The install went a little off, and went into a black screen with a non-responsive mouse visible.
A hard restart brought the system on line, and showing the driver had installed. Again, no luck with the program loads, which had started the whole troubleshooting odyssey. (Many many pages looked at, with many different suggested fixes) I would have pushed my system back to a restore point before all this mess, but it couldn’t access the restore point. Possibly an indication of something being out of whack?
My system has gone through multiple operating systems over many years, and I decided this might be a good justification to clear everything with a clean OS install. So, I bite the bullet and installed Win10 to my SSD and started with a clean slate. Windows pulled up an older graphics driver to load in, and my system went from the one screen back to multi. Next I fished out the 372.90 and began installing that. It started out fine, then dove into the black screen.
A hard restart, and it started entering a pattern where it would work for 2 seconds then go to a black screen for a minute or so. The mouse would also go into and out of responsiveness, as if the OS was blinking on, and blinking off. The timing made it impossible to reboot in safe mode (Since fast booting and an SSD made the keyboard shortcut unworkable). After another reinstall of windows, I saw the same problem reappear when Windows auto installed a 2015 version of the Nvidia drivers.
Finally seeing a mention of a similar problem being traced to multiple monitors, I disconnected the other three monitors connected to the system, and suddenly my system was working fine on a single monitor. I installed the 372.90 Nvidia driver, and after rebooting just to check all was perfect on the single monitor set-up. I tried hooking up one of the other monitors as a test, and when I went to detect it, my main monitor started going once again into the cycle of long black pauses. I was able to regain 1 monitor functionality by disconnecting the second monitor and rebooting, but this is a very bad situation for me.
What might be causing my problems? I thought it was the 372.90 but even on older drivers it is not letting me work with more than one monitor now. I would have thought the clean install of windows would have cleared away any conflicting code, but no. My cards have been solid, so I didn’t think it was hardware related. I’ve been on these monitors for years without problem. What started as an error problem loading a few graphics intensive programs has now smothered my whole system.
Do you have any ideas of a possible solution, or at least a way to diagnose the problem?

:)

 

Adding a second monitor to a pc using Windows 10

Windows 10 (and Windows 7 Pro) supports multiple monitors natively out of the box, you did not need any other version of Windows. Only Windows 7 Starter edition would not support dual display

In most cases the limitation is with the hardware. Not all graphics cards will support multiple displays and some motherboards will completely disable the on board graphics if an add on graphics card is installed. This prevents installing a single display
card and installing a second monitor on the motherboard.

If the display card only has the white DVI port provided it is the DVI-I specification it will support both a DVI and VGA display at the same time using a splitter cable. Virtually all modern graphics cards support multiple monitors.

 

Ms. Smith

All of a sudden, my computer screen has turned from white to neon pink. I have tried to change it back, but it will not change. The problem is not with my monitor or graphics card either.

 

NO idea , not really as I don't run AMD or Adobe but my 970 can run 4 monitors on its own ....3x DP and 1xHDMI without issues

I have the gigabyte G1 970 on 372.90 at the moment and it has run 3x 1080 DisplayPort for many years and added a 1440 res 32" in the middle instead a while back without issue.

perhaps pull the 760 and see what happens?