Windows 10: Dual Monitor flickering when extended

So I have bought a PC in July 2020.
I have an AMD Ryzen 5 3600 with a Radeon 5700 XT.
And for some reason when I connect a second display and put it on extended mode it starts to flicker every second until I turn it off again. It works if I use Radeon Eyeinfinty or what ever the name of it is, but I want to arrange my monitors so that it fits to my workflow and my style of gaming.
I have a 144hz monitor connected via displayport and a pen display 60 hz via a splitter cable that ends up in hdmi although the radeon software says its DVI D. But I don't think that this really matters because I had the same issue when I tried to use a TV as a second display.
Can somebody please help me out here, I'm just so frustrated at how this just is not working and it's reallystarting to get on my nerves.
I made recorded a video of the issue, but I can't seem to show it here, so if someone wants to help and needs a better understanding of my problem I'll provide the video via email or other sources!

:)

 

Trouble with 2 monitors

Hi Tim,

Thank you for posting your query in Microsoft Community.

I suggest you to change the settings to Extended Monitor and check if it helps.

Please follow below steps:

• Right Click any ware of the Desktop, and launch Personalization.
• Go to dual monitor settings under personalization, and change it Extended Monitor.

Please get back to us for future support, we’ll be glad to assist you further.



Thank you.

 

Windows 10 Dual Monitors Extended

Hi Julia,



Thank you for posting in Microsoft Community.

I regret for the inconvenience caused. I appreciate that you have tried a few troubleshooting steps. Let me help you resolve the issue.



I suggest you to check with the article created by Karthick Vengaloor
and see if it helps.

Windows 8.1 Extend dual monitor and resolution issue after update



And for a work around please go through the below article for further information.

Click on,
http://windows.microsoft.com/en-IN/windows-8/how-connect-multiple-monitors



I hope the information helps. If not, reply back with the details and updated status. We will be happy to assist you accordingly.

 

Extend Display to second and third monitors

Hi Ian,



Thank you for writing to Microsoft Community Forums.



I appreciate the efforts taken by you in resolving the issue. I understand that you are unable to extend the display to second or third monitor. I’ll certainly assist you with the issue.



However, it would be great if you can help us with the details requested below:

• What happens when you try to extend the display?
  
• Do you receive any error message/code?
  
• Are you aware of any changes made to the computer recently?
  
• Which build version of Windows 10 is installed on the computer? To check type:
  winver in the search bar on the Taskbar and hit
  Enter.
  
• What is the make and model of the laptop?
  

Ideally, to extend the display we can use the shortcut Windows logo key + P, and select
Extend from the menu.



I would suggest you to refer the troubleshooting steps mentioned in the article

Troubleshoot external monitor connections in Windows 10 and see if that helps.



For additional information, see
Set up dual monitors on Windows 10.



Let us know the results.



Regards,

Nikhar Khare

Microsoft Community - Moderator