[SOLVED] - Problem, Possible Xorg issue for my rig that uses MST on 1

Aha, so Wayland did make a difference! Hopefully the Radeon open source drivers will support that cause I know there’s a big community of people writing code for that. Maybe request it as a feature?

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Might have to, you know the github of any active opensource amdgpu repos? Unless Mesa request will do it.

You might try stepping down the res or refresh rate. Similar symptoms can occur from dodgy cables.

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Not sure if that would work if it works fine on windows 10 with all 6 monitors. But I guess wouldnt hurt to try, I’ve put as many monitors on the GPU i can get the MST hub down to only 2. With DVI on GPU.

id start off trying out ‘xrandr -q’ and see if your GPU even see there is 6 monitors.

You could see about getting a RX 560 cause Multi-GPU Wayland works with Fedora out of the box. That’s something impossible on Xsserver.

Posting to indicate I’m having a similar issue with MST on Fedora 27 (X11).

2x Dell monitors (U2415H), DP MST on a 580. Fully updated kernel. In this situation, the output is mirrored on both monitors.

Yeah, that’s what my MST hub does too. Also on fedora 27.

I previously had ubuntu, which didn’t recognize the hub at all or any monitors connected to it. At least with fedora it recognizes the other monitors and displays. Just wish it extended not mirrored.

Do you think I assume you mean in crossfire? I only have a 280x spare atm I guess I could pickup a 560, but then again I bought this MST HUB to do what the extra card would do… but prob be my last resort.

Tho, on second hand another gpu could help with lag with so many monitors. Anyone know the ram usage per monitor on average?

The 560 would be more energy efficient, but I’m not talking about Crossfire, I’m only talking about having a second low power GPU with enough ports to satisfy the rest of your monitors, and it looks like with Wayland, they finally fixed multiple displays over multiple GPUs, something impossible with Xorg.

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Not in crossfire? Just putting in another pci-e slot? So I could put in my 280x and would work too? Rather not care about power. If i already got it. Prob wouldnt be using much if only 1 monitor plugged into it. I got an older GTX 460 too but would that cause conflictions with AMD + Nvidia?

GTX 460 would conflict nouveau with amdgpu. Just putting the 280X in a secondary slot is all you need.

Cool mate thx. ill do that now I got a spare modular 750w PSU so ill prob have to use that. ill report back when im done.

So i put the 280x in and no joy. Wouldnt even let me in the login, monitors stayed black. It kept flashing each time i tried to log into fedora user login area to desktop and would keep going back to password till i unplugged the heads on the 280X GPU

Wait TAKE THAT BACK GOT IT WORKING! Had to change some plugs out!

Ok so one thing I am noticing however, I assume the drivers for R9 280x are shit or something. Or maybe I need to reseat the GPU cuz its getting artifacting on some logins.

It takes ages to get it to correct but it does. I can put up with that… lol

Basically when I login to Fedora it goes crazy setting up the x6 monitors, the monitor on the 280x just kinda artifacts some times on login so I log back out and back in till it corrects.

Now… Only if i can find that MST hub packages i can refund this thing… I think i threw them away so, w/e I’ll keep the MST Hub till linux gets supported better on them. I’d like to thank you all for the help. Much appreciated been running around for a week trying to get this going.

Now I can get back to work on my Crypto Trading :smiley:

Thought id show the finished copy.

So depending on your distro, you will need the latest firmware for the 280X. The 280, 280x, 380, 380x, and 390 cards have some quirkiness depending on the kernel that you are on. With debian this would look like apt install linux-firmware linux-firmware-nonfree

If you are using xorg, you will need to install and configure your monitors with xRandR. If you are using wayland, you need to ensure that you are using the most recent mesa and libdrm for radeon. Going one step further, since you a mixing a device that uses amdgpu and another that defaults to radeon, you may want to get the 280X on the amdpgu driver as well. The radeon and amdgpu drivers both use the radeonsi renderer in the back end. Your artifacting could be a conflict over shared libraries between the two drivers.

https://wiki.archlinux.org/index.php/AMDGPU#Enable_Southern_Islands_.28SI.29_and_Sea_Islands_.28CIK.29_support

They did. It’s actually quite good in my experience, but I’ve been unable to get F27 to launch GDM (or Gnome, for that matter) in Wayland. Does anyone know if they encountered some show-stopping issue and disabled it?

I’ve done this in the past, GTX 660 with R9 380. Worked fine around Linux 4.7.


All you had to do was change a cable? I wonder if I’m encountering the same issue. :thinking:

@SgtAwesomesauce, the wise Wendell had mentioned that :slight_smile:

Hmmm, time to visit the all-powerful Amazon wizard for assistance.

I also have a message into AMD support directly to see if they have any insight on if it’s confirmed working on 4.14. (should probably note that MST worked on my nvidia GPU previously, but it died)