4 display PC - 3 working, 1 detected but wont "extend display"

Danielrocha08

Commendable
Jun 12, 2016
20
0
1,510
Hi everyone.

I'm using a Sapphire Radeon HD 6900 series GPU along with an i5-7400 - 16GB DDR4 RAM - B250M Gaming Pro Mobo and Win10 256 SSD.

There are 5 ports in the back for display:
1x HDMI
2x DVI
2x Mini Display Ports.

Currently plugged in:
2x DVI to HDMI on the BOTTOM monitors and it works fine.
1x Active Mini DP to HDMI on the top right monitor and it works fine.
1x Active Mini DP to HDMI on the top left monitor, and it will not show display.

Display settings show all 4 monitors(3 display and 1 not displayed) and when I go to the settings for the one that IS NOT displaying, it has resolution, scaling and other options grayed out and shows "Disabled Display." When I choose "Extend these displays" on the same drop down menu, i click Keep changes and the display still doesn't show up.

In AMD Catalyst Control, it shows all 4 displays are "Identified" just like the window display settings.

Any ideas?

Thanks in advance.
 
Solution
I think there is a limitation on older cards for 3 active monitors, regardless of the number of possible attachments.
A cursory search did not show me this for certain.