thank you for for the help rather than flaming me instantly for trying to game on a server.
Ha! I have family that races Super Stock Trucks, round and round, in a truck? You'll find that ill-fated machine of yours will do fantastic. You'll find that you can get 99% out of that card in that butchered slot. You'll find you need an air conditioner...
Onwards, considering the matrox, it's in all vendors 5500/5520 series servers. A jumper is better, but if the bios allows disable great, use it. Without a jumper or bios disable it's likely the matrox address will be enumerated first - that's bad, it means default fallback actions will always have that matrox in the way and will force you to use a declaration file. I wired a spdt toggle to my jumper for play.
You can force the matrox like this, I tried 1920*1200 and it was offset to the left...I think 1080 worked, but settled on 1368*768 since it scaled well on my 1200p monitor.
Ask the computer how it sees the match with cvt
cvt 1360 768
the return will be...
# 1360x768 59.80 Hz (CVT) hsync: 47.72 kHz; pclk: 84.75 MHz
Modeline "1360x768_60.00" 84.75 1360 1432 1568 1776 768 771 781 798 -hsync +vsync
Then add the modes using the returned modeline:
xrandr --newmode "1360x768_60.00" 84.75 1360 1432 1568 1776 768 771 781 798 -hsync +vsync
Those will add to the available resolutions but still recommend not using the matrox unless you use it for a host/vm and use the amd in the vm. In that case, after learning that art, a similar declaration file needs to be in the vm.
More clear: some declaration I speak of is a file is where you found those generics tweaks, that file doesn't exist until you add it. Add a file named 52-somthing.conf to force xorg to your wishes. If you are wrong here you will be dumped to a prompt, so get ready to log on as root and...
the "52-" part is a priority, I like 52. that and the name can be whatever...
Also note you can create this file with competing sections commented out so you can track multiple tries.
And note you need to find the pci BUSID, and the exact layout may not be exact here...
Identifier “Default Screen”
Simply put, disabling the matrox avoids all of this headache and allows the autodetection to function correctly. Good luck!
And to add preemptively, once you rely on auto detection I can't help if the free AMD driver does or does not automagically configure the second port on the amd card. I use the free nouveau and it does...
and load your distro's firmware-amd-graphics...