I have a Radeon (TM) Pro WX 5100 Graphics.
My Radeon Pro Settings shows Display 3 correctly, but Display 4 isn't properly getting recognized.
It shows Display 3 as DELL U2718Q, but Display 4 as DDC Display.
My monitors are all connected using mDP to DP and I've just tried a brand new cable, same thing.
Even Windows seems to be confused by this fourth monitor and doesn't allow me to change resolution or anything.
On the monitor itself, it's a black screen that continues scanning for signal, then eventually says "No mDP signal from your device".
Unplugging the mDP cable from the monitor or computer gives me the "disconnected device Windows sound" and removes the mini box from the Display settings on the computer.
How can I resolve this issue?