X not working with TITAN V with Ubuntu 18.04

Hi,

I’m setting up a new PC with a TITAN V and Ubuntu 18.04. I installed nvidia-driver-430 from graphics-drivers PPA, as per instructions here:

https://linuxconfig.org/how-to-install-the-nvidia-drivers-on-ubuntu-18-04-bionic-beaver-linux

430 was the driver recommended by

$ ubuntu-drivers devices

X doesn’t start on TITAN output, only on motherboard Intel graphics. The TITAN output just shows a single underscore character. Key indicator of problem that I can find is in /var/log/Xorg.0.log:

(EE) Failed to load module "nvidia" (module doesn't support this OS, 0)

nvidia-bug-report.log.gz (1.11 MB)

Please downgrade to the stable v418 driver to rule out a bug with th v430 beta.

I’ve done this now, with no change in behaviour:

~ sudo apt-get purge nvidia\* ~ sudo apt-get install nvidia-driver-418
~$ sudo reboot

I still get “(EE) Failed to load module “nvidia” (module doesn’t support this OS, 0)” and

~$ glxinfo | grep OpenGL
OpenGL vendor string: VMware, Inc.

I’m attaching the new bug report output with the 418 driver.
nvidia-bug-report.log.gz (1.15 MB)

Now that’s really weird. Please replace your xorg.conf with just this snippet

Section "Device"
    Identifier     "nvidia"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BusID          "PCI:101:0:0"
    Option         "AllowEmptyInitialConfiguration"
EndSection

to check if the onboard graphics interferes. You should also mail the nvidia-bug-report.log and a description to linux-bugs[at]nvidia.com

That worked. X runs now on the TITAN output. Seems like there’s a bug in there somewhere(?). Thanks!

Also, can you tell me where the 101 comes from in the above xorg.conf file? Is that something you just knew, or read from some other information in the bug report data?

101 is the pci bus id of the Titan in decimal. Output from lspci:

65:00.0 VGA compatible controller [0300]: NVIDIA Corporation GV100 [TITAN V] [10de:1d81] (rev a1)

65hex=101dec
It’s also shown in the xorg logs.
This is definitely a bug but I don’t know either whether in the nvidia module or the Xserver.