So my issue is that, after each system reboot the NUMBER assinged to each Video Output on my GPU changes.
I start my computer up for the first time today, I have 5× Monitors attached to it, 4× Monitors are attached to the primary GPU which is a AMD Radeon VII 16GB, the 5th Monitor is connected to the computer via a Secondary GPU which is a AMD Radeon HD 7770GHz Edition 2GB
When the computer loads up the SDDM Login screen after turning on only 4 of the Monitors render any visuals, they are the 4 Monitors that are connected to the PC via the AMD Radeon VII 16GB GPU, during the login screen I can seamlessly navigate across all 4× Montiors in the correct order without any issues.
So, I login to my KDE Desktop session, and as it loads up the order in which my monitors are displayed changes, at the same time because I am now loading into the desktop session the 5th and final monitor which is connected to my secondary GPU comes into life and displays the relevant visuals.
Here is also where things go wrong, the monitors start displaying in an incorrect order, where the monitor to the left on centre identified hence forth as Monitor No.001 (Connected to the 1st DisplayPort Output on my Radeon VII) starts showing what should be on the central monitor which is Monitor No.002 (Connected to the 2nd DisplayPort Output on my Radeon VII), and on occasion, Monitor No.002 will display what is also being displayed on Monitor No.003 which is the monitor right of the centre (Connected to the 3rd DisplayPort Output on my Radeon VII).
Now each time I reboot my system this order changes around, on rare occasions it will display correctly but this is completely by chance, &, not by intention, which is what it should be doing.
The only behaviour that is consistently the same regardless of how many times I reboot are;
The 4th Monitor (Monitor No.004) which is connected to the Radeon VII’s one & only HDMI output port, and the 5th Monitor (Monitor No.005) which is connected to the AMD Radeon HD 7770GHz Edition’s DVI Port, DO NOT RESET or CHANGE OUTPUT, the ALWAYS WORK AS INTENDED!
Even though nothing gets changed physically at all, the DisplayPort-0/DisplayPort-1/DisplayPort-2/DisplayPort-3/DisplayPort-4 numbers that get assigned to the Monitors No.001/No.002/No.003, ALWAYS change. So although right now Monitor No.001 is assigned DisplayPort-0, on the next reboot it could be assigned as DisplayPort-2, the same issue also occurs with the other two Monitors that are connected via DisplayPort to the Radeon VII (Monitor No.002 & Monitor No.003).
So, right now I am lost as to what I can do to stop the DisplayPort outputs from changing their assinged numbers on every reboot.
Because that is what causes the displays to appear incorrectly.
I have already tried buying a DisplayPort MST Hub but that didn’t resolve any of the issues because the DisplayPort Numbers are still reassigned differently on every reboot.
If anybody has any advice that they can give me then please do let me know!