2 Monitor support suddenly broken

Linux Mint 19.3 Tricia (Ubuntu 18.04), GForce RTX 2080 TI OC 11G with two Iiyama 30" Monitors via Displayport.

I’ve got a strange issue since last evening. Did some updates, Kernel 4.15.0-1nvidia-bug-report.log.gz.txt (798.7 KB) 22 generic (because the 2080 has strange issues with Kernel 5.x).

After reboot, both monitors went dark when starting the nvidia driver. After a while I found out: removing one of the two DP cables gives the image back on one monitor.

Updated the NVIDA driver to 455, reverted to kernels up to 4 versions before - nothing changed.

Could this be a hardware problem? It worked flawlessly since September 2019 .

Berndnvidia-bug-report.log.gz.txt (798.7 KB)

Please run nvidia-bug-report.sh as root and attach the resulting nvidia-bug-report.log.gz file to your post.

created debugfile but forgot upload. missing my 2nd monitor for multitasking :(

Did you try downgrading the driver?
Please check if using the kernel parameter ‘nvidia-drm.modeset=1’ helps.

Sorry for the delay, had to prepare my software for yearly stocktaking…

I tried nvidia-drm.modeset=1, but nothing changed.

Reverted to driver 440.31 from October 2019, everything was fine again (see logfile).

Went to 450.80.02 again (which worked since November 2020), both monitors are black until I unplug one of them. Created a logfile with both monitors dark.

Its easy to switch drivers to provoke the problem:

  1. open tty1
  2. service lightdm stop
  3. start installer
  4. as soon the question-window “update xorg.conf” comes on screen, both monitors are working or they don’t

I followed the usual logfiles in /var/log and dmesg while plugging cable in and out, no messages.

driver_440.31.log.gz (1.1 MB)
driver_450.80.02.log.gz (1.0 MB)