Slight screen Flicker

I recently updated to a 4K UHD monitor. I have two other Acer 1080p monitors hooked into the same graphics cards. I randomly get a slight faint flicker in both the 1080p monitors. I've tried various methods to narrow it down but I'll try to mention all that I've tried. I'm really hoping it's a setting and not a faulty card. I've attempted thus far:

Doing an in place upgrade to just basically reinstall windows and not lose all your programs and settings
I've performed the latest Win 10 updates
I've upgraded the Nvidia Card driver and tried both the game driver and studio driver.
I've tried an older Nvidia driver
I've tried replacing the PC display cables and trying a different port on the back of the card
I've tried replacing the monitor with another monitor laying around.
I've tried recording it to see if my eyes are going buggy and can't seem to get it on a phone, nor can I obtain it off a screen recording program such as the one that comes with GeForce Experience
I've tried making sure the card is set in place in the PCI express lane

I'm leaning on this is a setting within Windows Display and or Nvidia Control panel? I was hoping it was a refresh rate problem, but the 4k monitor is the only one that I can change and can only go down from 60Hz. The 1080p monitors only have 60Hz.

I do mainly notice the issue in Photoshop being a designer, and taking advantage of the three monitors, I thought possibly that spreading a program across two different resolutions might have an effect? I main put the tool panels on the 1080p monitor and edit on the 4k. Is this possible?

Any and all suggestions is greatly appreciated! I guess I didn't think too much into when I made the purchase, I didn't think it would cause such issues.

Screen problems are mostly caused by graphic drivers,suggest you check Reliability History for an entry which mentions TDR [timeout detection and recovery].
The default time is 2 seconds and is given in milliseconds in the registry---HKLM\system\controlset 001\control\graphic drivers---
This can be changed,if you enjoy messing with the registry.
I suspect,but cannot prove that the 4k monitor is most likely to be the culprit.Please be aware I have not had any dealings with these new monitors,so treat the above with scepticism.
The only other suggestion is to uninstall/reinstall the display adapter driver using Display Driver Uninstaller [DDU] in safe mode.
In the search box,type in---dxdiag---and use the driver version given on the display page.

What graphics card do you have? It might be that it cannot have enough power to drive three monitors, one being 4K. Try to lower the refresh rate in 4K, it might work. Also trying to drive three monitors the card draws more power and it might be that your PSU is not good enough. You could upgrade to a model with more Watts.