@XpertVolvox
If OS auto EDID detection for multi display configuration failed, then need update monitors information manually, carry out following procedures.
For example, monitor default resolution is 1920 x1080,
1, step down resolution to 1280 x 720, then reboot
2, from 1280 x 720 step up to 1600 x 900, then reboot
3, after reboot resolution is 1600 x 900 then stop, shutdown.
Repeat above steps to 2nd port / 2nd monitor and so on for 3rd port / 3 rd monitor.
Now EDID information should enough for multi monitor application.
Make sure all ports and monitors are set at 1600 x 900 before hotplug monitor test.
If OK, then switch back to monitor best resolution 1920 x1080.