AMD RX 570 with triple monitor setup

Help
1

I initially did nothing specific after physically installing the card and it pretty much worked out of the box - all three monitors were usable individually and with their correct resolution. I’ve been using the setup a few days.

I then (had to) start a windows vm (with virtualbox) which did not work - my de hang and I could not use the pc anymore. After rebooting, All my monitors were at 640x320 resolution, mirrored and I only got two of three to 1920x1080.
Since then I’ve tried a few things, but could not get it to work.
Notably I found this thread and this github issue and tried the configuration proposals there.

This thread suggests using the amdgpu pro drivers which I tried with no luck.

System information
[nix-shell:~]$ sudo inxi -F
System:    Host: kolamaschinenix Kernel: 5.4.33 x86_64 bits: 64 Desktop: i3 4.17.1 
           Distro: NixOS 20.03.1596.2faa76db27c (Markhor) 
Machine:   Type: Desktop Mobo: ASUSTeK model: M5A78L-M/USB3 v: Rev X.0x serial: 131219467600718 BIOS: American Megatrends 
           v: 2001 date: 09/11/2014 
CPU:       Topology: 8-Core model: AMD FX-8350 bits: 64 type: MCP L2 cache: 2048 KiB 
           Speed: 1596 MHz min/max: 1400/4000 MHz Core speeds (MHz): 1: 1567 2: 2701 3: 1475 4: 1521 5: 1746 6: 3416 7: 2083 
           8: 2469 
Graphics:  Message: No Device data found. 
           Display: server: X.org 1.20.8 driver: resolution: <xdpyinfo missing> 
           OpenGL: renderer: Radeon RX 570 Series (POLARIS10 DRM 3.35.0 5.4.33 LLVM 9.0.1) v: 4.5 Mesa 19.3.3 
Audio:     Device-1: HDA ATI SB driver: HDA-Intel 
           Device-2: HDA ATI HDMI driver: HDA-Intel 
           Sound Server: ALSA v: k5.4.33 
Network:   Message: No Device data found. 
           IF-ID-1: docker0 state: down mac: 02:42:57:a2:44:38 
           IF-ID-2: enp3s0 state: up speed: 1000 Mbps duplex: full mac: e0:3f:49:18:92:ee 
           IF-ID-3: vboxnet0 state: down mac: 0a:00:27:00:00:00 
Sensors:   System Temperatures: cpu: 36.0 C mobo: 35.0 C gpu: amdgpu temp: 45 C 
           Fan Speeds (RPM): cpu: 705 case-1: 1146 gpu: amdgpu fan: 1022 
Info:      Processes: 214 Uptime: N/A Memory: 15.63 GiB used: 2.88 GiB (18.4%) Shell: zsh inxi: 3.0.37

Relevant part of my configuration.nix:

  boot.kernelPackages = pkgs.linuxPackages_5_4;
  boot.kernelParams = [ "amd_iommu=pt" "ivrs_ioapic[32]=00:14.0" "iommu=soft" ];
  boot.kernelModules = [ "kvm-intel" "kvm-amd" ];
 # boot.kernelParams = ["amdgpu.dc=1" "amdgpu.si_support=1"];
  services.xserver.videoDrivers = [ "amdgpu"  ];

  hardware = {
    cpu.amd.updateMicrocode = true;
    enableRedistributableFirmware = true;
    opengl.enable = true;
    opengl.driSupport = true;
  };

xrandr tells me that the one display that is still running at 640x480 only has that resolution:

Screen 0: minimum 320 x 200, current 4480 x 1080, maximum 16384 x 16384
DisplayPort-0 connected 640x480+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   640x480       59.94* 
DisplayPort-1 connected 1920x1080+2560+0 (normal left inverted right x axis y axis) 598mm x 336mm
   1920x1080     60.00*+  50.00    59.94  
   1680x1050     59.88  
   1280x1024     75.02    70.00    60.02  
   1440x900      59.90  
   1280x800      60.00  
   1152x864      75.00  
   1280x720      60.00    50.00    59.94  
   1024x768      75.03    70.07    60.00  
   800x600       72.19    75.00    60.32  
   720x576       50.00  
   720x480       60.00    59.94  
   640x480       75.00    72.81    60.00    59.94  
   720x400       70.08  
DisplayPort-2 disconnected (normal left inverted right x axis y axis)
HDMI-A-0 connected primary 1920x1080+640+0 (normal left inverted right x axis y axis) 598mm x 336mm
   1920x1080     60.00*+  74.97    50.00    59.94  
   1680x1050     59.88  
   1280x1024     75.02    70.00    60.02  
   1440x900      59.90  
   1280x800      60.00  
   1152x864      75.00  
   1280x720      60.00    50.00    59.94  
   1024x768      75.03    70.07    60.00  
   800x600       72.19    75.00    60.32  
   720x576       50.00  
   720x480       60.00    59.94  
   640x480       75.00    72.81    60.00    59.94  
   720x400       70.08  
DVI-D-0 disconnected (normal left inverted right x axis y axis)
2

Now I’ve disabled the part in my configuration.nix graphics driver part completely, rebooted and couldn’t even get to the login screen. My displays were completely black, but turned on.
This is especially interesting since it worked that way before I started changing things.

After rebooting and selecting an older nix generation from grub, I found a few things in the log:
(The bluetooth stuff is probably unrelated)

Apr 28 22:18:11 kolamaschinenix bluetoothd[1127]: Sap driver initialization failed.
Apr 28 22:18:11 kolamaschinenix bluetoothd[1127]: sap-server: Operation not permitted (1)


Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) Using config directory: "/etc/X11/xorg.conf.d"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) Using system config directory "/nix/store/5lfs07qnfyfqvwfj9vix43gx6937pv0x-xorg-server-1.20.8/share/X11/xorg.conf.d"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) ServerLayout "Layout[all]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |-->Screen "Screen-radeon[0]" (0)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Monitor "<default monitor>"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Device "Device-radeon[0]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) No monitor specified for screen "Screen-radeon[0]".
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         Using a default monitor configuration.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |-->Screen "Screen-cirrus[0]" (1)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Monitor "<default monitor>"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Device "Device-cirrus[0]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) No monitor specified for screen "Screen-cirrus[0]".
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         Using a default monitor configuration.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |-->Screen "Screen-vesa[0]" (2)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Monitor "<default monitor>"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Device "Device-vesa[0]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) No monitor specified for screen "Screen-vesa[0]".
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         Using a default monitor configuration.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |-->Screen "Screen-vmware[0]" (3)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Monitor "<default monitor>"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Device "Device-vmware[0]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) No monitor specified for screen "Screen-vmware[0]".
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         Using a default monitor configuration.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |-->Screen "Screen-modesetting[0]" (4)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Monitor "<default monitor>"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Device "Device-modesetting[0]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) No monitor specified for screen "Screen-modesetting[0]".
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         Using a default monitor configuration.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) Option "DontZap" "on"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) Option "AllowMouseOpenFail" "on"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) Automatically adding devices
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) Automatically enabling devices
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) Automatically adding GPU devices
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) Max clients allowed: 256, resource mask: 0x1fffff
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) FontPath set to:
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/8z6hhpdydg0kz2my3rln8ws11lxhiz29-font-bh-lucidatypewriter-100dpi-1.0.3/lib/X11/fonts/100dpi,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/syxva6hnm3yfap3x6wiv0vw1q9zchzh0-font-bh-lucidatypewriter-75dpi-1.0.3/lib/X11/fonts/75dpi,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/dgl1mrqdxngj3wg1wxrmn3wyzb9dvvqw-font-bh-100dpi-1.0.3/lib/X11/fonts/100dpi,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/p64h8x8nyjrzr9p6hd42mq48chlm7dgz-font-misc-misc-1.1.2/lib/X11/fonts/misc,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/fv5558j29cy4k7xcyv7i1sdck0r632jr-font-cursor-misc-1.0.3/lib/X11/fonts/misc,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/nyx1r5a0vnw0s84p8nh1mqcln89rm3rl-unifont-12.1.03/share/fonts,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/6qawpymllf3djprwqnfzjq0g5lq8fcp6-font-adobe-100dpi-1.0.3/lib/X11/fonts/100dpi,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/0rmd6bzd3lg0fl1qs4xj8fhr377wcl8a-font-adobe-75dpi-1.0.3/lib/X11/fonts/75dpi
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) ModulePath set to "/nix/store/hihwlcic52bwxj9w7gvwvahdgqz455vf-xf86-video-ati-19.0.1/lib/xorg/modules/drivers,/nix/store/ipfi10b5hnal0q8kdj47273w8xpha465-xf86-video-cirrus-1.5.>
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (II) The server relies on udev to provide the list of input devices.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         If no devices become available, reconfigure udev or disable AutoAddDevices.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (II) Loader magic: 0x625d40
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (II) Module ABI versions:
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         X.Org ANSI C Emulation: 0.4
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         X.Org Video Driver: 24.1
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         X.Org XInput driver : 24.1
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         X.Org Server Extension : 10.0
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (++) using VT number 7
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (II) systemd-logind: logind integration requires -keeptty and -keeptty was not provided, disabling logind integration
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (II) xfree86: Adding drm device (/dev/dri/card0)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (--) PCI:*(1@0:0:0) 1002:67df:1682:c570 rev 239, Mem @ 0xd0000000/268435456, 0xcfe00000/2097152, 0xfeac0000/262144, I/O @ 0x0000d000/256, BIOS @ 0x????????/131072
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (WW) Open ACPI failed (/var/run/acpid.socket) (No such file or directory)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (II) "glx" will be loaded by default.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         to make sure that you have the latest version.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: Markers: (--) probed, (**) from config file, (==) default setting,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         (++) from command line, (!!) notice, (II) informational,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         (WW) warning, (EE) error, (NI) not implemented, (??) unknown.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (++) Log file: "/dev/null", Time: Tue Apr 28 22:18:12 2020
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (++) Using config file: "/nix/store/508xnyv8vcd2csxj8ncjizcwm4gr941w-xserver.conf"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) Using config directory: "/etc/X11/xorg.conf.d"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) Using system config directory "/nix/store/5lfs07qnfyfqvwfj9vix43gx6937pv0x-xorg-server-1.20.8/share/X11/xorg.conf.d"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) ServerLayout "Layout[all]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |-->Screen "Screen-radeon[0]" (0)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Monitor "<default monitor>"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Device "Device-radeon[0]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) No monitor specified for screen "Screen-radeon[0]".
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         Using a default monitor configuration.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |-->Screen "Screen-cirrus[0]" (1)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Monitor "<default monitor>"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         Using a default monitor configuration.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) ServerLayout "Layout[all]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |-->Screen "Screen-radeon[0]" (0)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Monitor "<default monitor>"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Device "Device-radeon[0]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) No monitor specified for screen "Screen-radeon[0]".
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         Using a default monitor configuration.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |-->Screen "Screen-cirrus[0]" (1)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Monitor "<default monitor>"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Device "Device-cirrus[0]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) No monitor specified for screen "Screen-cirrus[0]".
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         Using a default monitor configuration.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |-->Screen "Screen-vesa[0]" (2)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Monitor "<default monitor>"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Device "Device-vesa[0]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) No monitor specified for screen "Screen-vesa[0]".
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         Using a default monitor configuration.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |-->Screen "Screen-vmware[0]" (3)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Monitor "<default monitor>"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Device "Device-vmware[0]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) No monitor specified for screen "Screen-vmware[0]".
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         Using a default monitor configuration.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |-->Screen "Screen-modesetting[0]" (4)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Monitor "<default monitor>"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) |   |-->Device "Device-modesetting[0]"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) No monitor specified for screen "Screen-modesetting[0]".
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         Using a default monitor configuration.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) Option "DontZap" "on"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) Option "AllowMouseOpenFail" "on"
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) Automatically adding devices
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) Automatically enabling devices
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) Automatically adding GPU devices
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (==) Max clients allowed: 256, resource mask: 0x1fffff
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) FontPath set to:
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/8z6hhpdydg0kz2my3rln8ws11lxhiz29-font-bh-lucidatypewriter-100dpi-1.0.3/lib/X11/fonts/100dpi,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/syxva6hnm3yfap3x6wiv0vw1q9zchzh0-font-bh-lucidatypewriter-75dpi-1.0.3/lib/X11/fonts/75dpi,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/dgl1mrqdxngj3wg1wxrmn3wyzb9dvvqw-font-bh-100dpi-1.0.3/lib/X11/fonts/100dpi,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/p64h8x8nyjrzr9p6hd42mq48chlm7dgz-font-misc-misc-1.1.2/lib/X11/fonts/misc,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/fv5558j29cy4k7xcyv7i1sdck0r632jr-font-cursor-misc-1.0.3/lib/X11/fonts/misc,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/nyx1r5a0vnw0s84p8nh1mqcln89rm3rl-unifont-12.1.03/share/fonts,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/6qawpymllf3djprwqnfzjq0g5lq8fcp6-font-adobe-100dpi-1.0.3/lib/X11/fonts/100dpi,
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         /nix/store/0rmd6bzd3lg0fl1qs4xj8fhr377wcl8a-font-adobe-75dpi-1.0.3/lib/X11/fonts/75dpi
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (**) ModulePath set to "/nix/store/hihwlcic52bwxj9w7gvwvahdgqz455vf-xf86-video-ati-19.0.1/lib/xorg/modules/drivers,/nix/store/ipfi10b5hnal0q8kdj47273w8xpha465-xf86-video-cirrus-1.5.>
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (II) The server relies on udev to provide the list of input devices.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         If no devices become available, reconfigure udev or disable AutoAddDevices.
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (II) Loader magic: 0x625d40
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (II) Module ABI versions:
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         X.Org ANSI C Emulation: 0.4
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         X.Org Video Driver: 24.1
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         X.Org XInput driver : 24.1
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]:         X.Org Server Extension : 10.0
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (++) using VT number 7
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (II) systemd-logind: logind integration requires -keeptty and -keeptty was not provided, disabling logind integration
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (II) xfree86: Adding drm device (/dev/dri/card0)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (--) PCI:*(1@0:0:0) 1002:67df:1682:c570 rev 239, Mem @ 0xd0000000/268435456, 0xcfe00000/2097152, 0xfeac0000/262144, I/O @ 0x0000d000/256, BIOS @ 0x????????/131072
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (WW) Open ACPI failed (/var/run/acpid.socket) (No such file or directory)
Apr 28 22:18:12 kolamaschinenix xserver-wrapper[1305]: (II) "glx" will be loaded by default.


Apr 28 22:18:27 kolamaschinenix systemd[1]: NetworkManager-dispatcher.service: Succeeded.
Apr 28 22:18:35 kolamaschinenix nscd[1404]: 1404 checking for monitored file `/etc/netgroup': No such file or directory
Apr 28 22:18:41 kolamaschinenix systemd-timesyncd[1119]: Initial synchronization to time server [2a03:4000:6:e34b:7cf3:194b:368:22d]:123 (2.nixos.pool.ntp.org).
Apr 28 22:18:42 kolamaschinenix systemd[1]: systemd-hostnamed.service: Succeeded.
Apr 28 22:19:47 kolamaschinenix sddm-greeter[1350]: Reading from "/nix/store/195iaag1ixf7p9my1zan5zf6s5l5gnw8-desktops/share/xsessions/none+i3.desktop"
Apr 28 22:19:47 kolamaschinenix sddm-greeter[1350]: Loading theme configuration from "qrc:/theme/theme.conf"
Apr 28 22:19:47 kolamaschinenix sddm-greeter[1350]: Connected to the daemon.
Apr 28 22:19:47 kolamaschinenix sddm[1303]: Message received from greeter: Connect
Apr 28 22:19:47 kolamaschinenix sddm-greeter[1350]: Loading qrc:/theme/Main.qml...
Apr 28 22:19:47 kolamaschinenix sddm-greeter[1350]: Adding view for "DP-1" QRect(0,0 640x480)
Apr 28 22:19:47 kolamaschinenix sddm-greeter[1350]: Loading qrc:/theme/Main.qml...
Apr 28 22:19:47 kolamaschinenix sddm-greeter[1350]: Adding view for "DP-2" QRect(0,0 640x480)
Apr 28 22:19:47 kolamaschinenix sddm-greeter[1350]: Loading qrc:/theme/Main.qml...
Apr 28 22:19:47 kolamaschinenix sddm-greeter[1350]: Adding view for "HDMI-1" QRect(0,0 640x480)
Apr 28 22:19:47 kolamaschinenix xserver-wrapper[1305]: (WW) modeset(0): flip queue failed: Device or resource busy
Apr 28 22:19:47 kolamaschinenix xserver-wrapper[1305]: (WW) modeset(0): Page flip failed: Device or resource busy
Apr 28 22:19:47 kolamaschinenix xserver-wrapper[1305]: (EE) modeset(0): present flip failed
Apr 28 22:19:47 kolamaschinenix xserver-wrapper[1305]: (WW) modeset(0): flip queue failed: Device or resource busy
Apr 28 22:19:47 kolamaschinenix xserver-wrapper[1305]: (WW) modeset(0): Page flip failed: Device or resource busy
Apr 28 22:19:47 kolamaschinenix xserver-wrapper[1305]: (EE) modeset(0): present flip failed
Apr 28 22:19:47 kolamaschinenix sddm-greeter[1350]: Message received from daemon: Capabilities
Apr 28 22:19:47 kolamaschinenix sddm-greeter[1350]: Message received from daemon: HostName
Apr 28 22:19:47 kolamaschinenix xserver-wrapper[1305]: (WW) modeset(0): flip queue failed: Device or resource busy
Apr 28 22:19:47 kolamaschinenix xserver-wrapper[1305]: (WW) modeset(0): Page flip failed: Device or resource busy
Apr 28 22:19:47 kolamaschinenix xserver-wrapper[1305]: (EE) modeset(0): present flip failed
Apr 28 22:20:00 kolamaschinenix xserver-wrapper[1305]: (WW) modeset(0): flip queue failed: Device or resource busy
Apr 28 22:20:00 kolamaschinenix xserver-wrapper[1305]: (WW) modeset(0): Page flip failed: Device or resource busy
Apr 28 22:20:00 kolamaschinenix xserver-wrapper[1305]: (EE) modeset(0): present flip failed
3

I switched the cables between the two monitors and now both are running at the right resolutions.

I suspected a faulty cable, to verify I used the cable of the third monitor (which was working as it should) and plugged it into the first (which was only working only with 640x480) and got it working in 1920x1080 - it seemed the original cable of the first was to blame. To verify that again, I plugged the cable from the first (the one I suspected to be broken) into the now cable-less third one and it worked with the resolution it should have.
So it does not seem like the cable is broken, or a monitor, or a the graphics card,
it just seems to be the old “have you tried turning it off and back on again?”

Now let’s see if it survives a reboot.

EDIT: It did survive a reboot

4

So, I got new cables (unrelated to this) and it works now. It seems it was just a bad cable after all -.-

Comment from the nix matrix channel:

The monitor communicates the resolution to the PC. If anything goes wrong during this communication, there must be a safe default, which in your case was 640x480. Looks like an electrical issue for me, because the cable is slighlty faulty, has a bend pin, an impedance mismatch, etc. In these communiction if any of the bits get mangeled, the checksum won’t match and the message is ignored.

6

I guess due to the nature of nix we always assume there’s something wrong with the configuration before checking the hardware :upside_down_face: