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CodeGhost avatar Ubuntu

Only one monitor working at a time - Ubuntu 20.04, Linux 5.11.-27, AMD CPU and 6700XT

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CodeGhost

So, I bought a 6700XT and plugged it into my PC. My second screen (HDMI connection) does not show up in any commands or the Ubuntu display settings. It seems that Ubuntu can somehow only connect 1 monitor at a time. I've figured out that it is probably software related because:

  1. Windows 10 is showing the monitor correctly (dual boot, no hardware changes)
  2. When I shutdown, disconnect the primary screen (Display port connection), and boot, it will correctly boot using the second screen. Then reconnected the primary, and it goes back to only using that.

I've installed and de-installed amd-gpu, to no avail. What could be going wrong here?

Commands & ouput:

xrandr

Screen 0: minimum 640 x 480, current 2560 x 1440, maximum 2560 x 1440
default connected primary 2560x1440+0+0 0mm x 0mm
   2560x1440      0.00* 
   1600x1200      0.00  
   1680x1050      0.00  
   1400x1050      0.00  
   1280x1024      0.00  
   1280x960       0.00  
   1024x768       0.00  
   800x600        0.00  
   640x480        0.00

sudo lshw -C video

       description: VGA compatible controller
       product: Advanced Micro Devices, Inc. [AMD/ATI]
       vendor: Advanced Micro Devices, Inc. [AMD/ATI]
       physical id: 0
       bus info: pci@0000:0c:00.0
       version: c1
       width: 64 bits
       clock: 33MHz
       capabilities: pm pciexpress msi vga_controller cap_list
       configuration: latency=0
       resources: memory:d0000000-dfffffff memory:e0000000-e01fffff ioport:e000(size=256) memory:fca00000-fcafffff memory:c0000-dffff

uname -r

5.11.0-27-generic

lsb_release -a

Distributor ID: Ubuntu
Description:    Ubuntu 20.04.3 LTS
Release:    20.04
Codename:   focal
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CodeGhost avatar Ubuntu
cn flag
CodeGhost

I found the solution: The older versions of amdgpu do not work with newer cards like the 6700XT. However, when I was googling the amdgpu driver, the first amd.com result was version 20.2 (june 2020). I used this url instead: https://www.amd.com/en/support/graphics/amd-radeon-6000-series/amd-radeon-6700-series/amd-radeon-rx-6700-xt

Which gave me version 21.30, and now both displays are working! Hope this helps a future 6700XT owner.

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