Multi-Monitor setup not working after updates

Hey folks,

I did a pacman -Syu and it broke my System. I’m running the 5.10 and the 455.45.01 nonfree nvidia driver.
After reboot my primary display stopped working and just my secondary works. I can’t change any settings in gnome-settings, but in nvidia-settings the primary display is disabled and I can activate it. It then shows just nvidia-settings windows and no gnome-gui. After a reboot I’m back where I started.

When I boot with just my primary display connected, I get a black screen with a mouse cursor and I can’t change to tty.

I tried to re-install the nvidia driver, but it didn’t help.

Any help?

    ~ >>> inxi --full --verbosity=7 --filter --no-host                             
    System:
      Kernel: 5.10.2-2-MANJARO x86_64 bits: 64 compiler: gcc v: 10.2.0 
      Desktop: GNOME 3.38.2 tk: GTK 3.24.24 wm: gnome-shell dm: GDM 3.38.2.1 
      Distro: Manjaro Linux 
    Machine:
      Type: Desktop System: ASUS product: N/A v: N/A serial: <filter> 
      Mobo: ASUSTeK model: PRIME Z490-A v: Rev 1.xx serial: <filter> 
      UEFI: American Megatrends v: 0607 date: 05/29/2020 
    Memory:
      RAM: total: 31.25 GiB used: 3.94 GiB (12.6%) 
      RAM Report: 
      permissions: Unable to run dmidecode. Root privileges required. 
    CPU:
      Info: 10-Core model: Intel Core i9-10900 bits: 64 type: MT MCP 
      arch: Comet Lake rev: 5 L2 cache: 20 MiB bogomips: 112043 
      Speed: 800 MHz min/max: 800/5200 MHz Core speeds (MHz): 1: 800 2: 800 
      3: 801 4: 801 5: 801 6: 800 7: 800 8: 800 9: 800 10: 800 11: 800 12: 800 
      13: 800 14: 800 15: 800 16: 800 17: 800 18: 801 19: 800 20: 800 
      Flags: 3dnowprefetch abm acpi adx aes aperfmperf apic arat 
      arch_capabilities arch_perfmon art avx avx2 bmi1 bmi2 bts clflush 
      clflushopt cmov constant_tsc cpuid cpuid_fault cx16 cx8 de ds_cpl dtes64 
      dtherm dts epb ept ept_ad erms est f16c flexpriority flush_l1d fma fpu 
      fsgsbase fxsr ht hwp hwp_act_window hwp_epp hwp_notify ibpb ibrs 
      ibrs_enhanced ida intel_pt invpcid invpcid_single lahf_lm lm mca mce 
      md_clear mmx monitor movbe mpx msr mtrr nonstop_tsc nopl nx ospke pae pat 
      pbe pcid pclmulqdq pdcm pdpe1gb pebs pge pku pln pni popcnt pse pse36 pts 
      rdrand rdseed rdtscp rep_good sdbg sep smap smep smx ss ssbd sse sse2 
      sse4_1 sse4_2 ssse3 stibp syscall tm tm2 tpr_shadow tsc tsc_adjust 
      tsc_deadline_timer vme vmx vnmi vpid x2apic xgetbv1 xsave xsavec xsaveopt 
      xsaves xtopology xtpr 
    Graphics:
      Device-1: NVIDIA vendor: Micro-Star MSI driver: nvidia v: 455.45.01 
      bus ID: 01:00.0 chip ID: 10de:2206 
      Display: x11 server: X.org 1.20.10 compositor: gnome-shell driver: nvidia 
      resolution: <missing: xdpyinfo> 
      OpenGL: renderer: GeForce RTX 3080/PCIe/SSE2 v: 4.6.0 NVIDIA 455.45.01 
      direct render: Yes 
    Audio:
      Device-1: Intel Comet Lake PCH cAVS vendor: ASUSTeK driver: snd_hda_intel 
      v: kernel bus ID: 00:1f.3 chip ID: 8086:06c8 
      Device-2: NVIDIA vendor: Micro-Star MSI driver: snd_hda_intel v: kernel 
      bus ID: 01:00.1 chip ID: 10de:1aef 
      Device-3: Logitech C505 HD Webcam type: USB driver: snd-usb-audio,uvcvideo 
      bus ID: 1-3:4 chip ID: 046d:08e3 serial: <filter> 
      Device-4: FiiO FiiO K5 Pro type: USB driver: snd-usb-audio 
      bus ID: 1-10.2:9 chip ID: 2972:0047 
      Sound Server: ALSA v: k5.10.2-2-MANJARO 
    ~~
      Processes: 371 Uptime: 26m wakeups: 0 Init: systemd v: 247 Compilers: 
      gcc: 10.2.0 Packages: 1402 pacman: 1398 snap: 4 Shell: Zsh v: 5.8 
      running in: gnome-terminal inxi: 3.2.01

And here is my xorg.conf:

# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings:  version 455.45.01

Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0" 3840 0
    Screen      1  "Screen1" LeftOf "Screen0"
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
    Option         "Xinerama" "1"
EndSection

Section "Files"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/psaux"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Keyboard0"
    Driver         "kbd"
EndSection

Section "Monitor"
    # HorizSync source: edid, VertRefresh source: edid
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "AOC G2460"
    HorizSync       30.0 - 160.0
    VertRefresh     30.0 - 150.0
    Option         "DPMS"
EndSection

Section "Monitor"
    # HorizSync source: edid, VertRefresh source: edid
    Identifier     "Monitor1"
    VendorName     "Unknown"
    ModelName      "Acer XB273K GP"
    HorizSync       510.0 - 510.0
    VertRefresh     48.0 - 120.0
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "GeForce RTX 3080"
    BusID          "PCI:2:0:0"
    Screen          0
EndSection

Section "Device"
    Identifier     "Device1"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "GeForce RTX 3080"
    BusID          "PCI:2:0:0"
    Screen          1
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    Option         "Stereo" "0"
    Option         "nvidiaXineramaInfoOrder" "DFP-5"
    Option         "metamodes" "DP-4: nvidia-auto-select +0+0"
    Option         "SLI" "Off"
    Option         "MultiGPU" "Off"
    Option         "BaseMosaic" "off"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

Section "Screen"
    Identifier     "Screen1"
    Device         "Device1"
    Monitor        "Monitor1"
    DefaultDepth    24
    Option         "Stereo" "0"
    Option         "metamodes" "DP-2: nvidia-auto-select +0+0 {AllowGSYNC=Off}"
    Option         "SLI" "Off"
    Option         "MultiGPU" "Off"
    Option         "BaseMosaic" "off"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

Hi Lain - I’ve got the exact same problem on my work machine.
This is the first time a manjaro update breaks my work setup and therefore productivity.

Where do I get these logs from?
I could add mine, too. Maybe this would help.

I found this thread stating the same problem with a great solution for the moment:

(I am not allowed to post links so it’s a pre formatted block now, sorry)
https://forum.manjaro.org/t/after-update-to-kernel-5-10-cannot-enable-external-monitor/46355/3

In grub I bootet back into Kernel 5.9 and everything works fine.
You could, sure, also try one of the other probable temporarily solutions given in the linked thread until multi monitor works good in 5.10 again.

Regards,
Horst