Dual Monitor Setup Not Working

[budest]

Hey guys,

Successful upgrade to HS bar a minor issue and that is that I can't have dual monitors running as I did with Sierra. I can only have one monitor connected at a time. If I connect the second monitor when the first is working fine the first monitor switches to display the second desktop and the second monitor just displays a black screen. When I disconnect the second monitor the first monitor reverts to displaying the main desktop. Hope that makes sense.


It's a weird one.


Prob should have noted that I am using a AMD Radeon 7 Series card with HDMI & DVI connections.

Any ideas?

 

[budest]

Hey guys,

Successful upgrade to HS bar a minor issue and that is that I can't have dual monitors running as I did with Sierra. I can only have one monitor connected at a time. If I connect the second monitor when the first is working fine the first monitor switches to display the second desktop and the second monitor just displays a black screen. When I disconnect the second monitor the first monitor reverts to displaying the main desktop. Hope that makes sense.


It's a weird one.


Prob should have noted that I am using a AMD Radeon 7 Series card with HDMI & DVI connections.

Any ideas?

I've narrowed it down to the DVI to HDMI being the issue.

Monitor 1 = Main monitor. Connected via HDMI - HDMI. Displaying Desktop 1
Monitor 2 = Second monitor. Connected via DVI - HDMI.

When Monitor 1 is solely connected everything is fine. When I connect monitor 2 monitor 1 display flips to second desktop and monitor 2 just displays a black screen.

 

[jcgamestoy]

I've narrowed it down to the DVI to HDMI being the issue.

Monitor 1 = Main monitor. Connected via HDMI - HDMI. Displaying Desktop 1
Monitor 2 = Second monitor. Connected via DVI - HDMI.

When Monitor 1 is solely connected everything is fine. When I connect monitor 2 monitor 1 display flips to second desktop and monitor 2 just displays a black screen.

I had exactly the same issue but with a NVidia GTX 970.

I fixed it, is a problem with the windows server configuration you need to delete:

/Library/Preferences/com.apple.windowserver.plist

and IMPORTANT you must delete also all the files :

~/Library/Preferences/ByHost/com.apple.windowserver.XXXXXXXXXXX.plist

reboot. the problem is fixed for me the two screens works now as expected.

I Hope this will help you.

 

[budest]

I had exactly the same issue but with a NVidia GTX 970.

I fixed it, is a problem with the windows server configuration you need to delete:

/Library/Preferences/com.apple.windowserver.plist

and IMPORTANT you must delete also all the files :

~/Library/Preferences/ByHost/com.apple.windowserver.XXXXXXXXXXX.plist

reboot. the problem is fixed for me the two screens works now as expected.

I Hope this will help you.

Hey thanks for your input. Unfortunately this doesn't resolve my issue.

 

[jcgamestoy]

Hey thanks for your input. Unfortunately this doesn't resolve my issue.

Sorry to hear that. You can try also to press cmd+f1 in the keyboard this will mirror both screens.

regards.