Can't get tunderbolt display to work

I am unable to get Cinnamon or Gnome desktops to use my thunderbolt display.

A little background:
Razer Blade 17 laptop
Razer Core 2 enclosure
Fedora 29 with 5.0 kernel
Nvidia 4.19 drivers installed.
nvidia-smi shows both the internal GPU and the 2080 graphics card.
xrandr --listproviders only shows the built in video gpu
nvidia-settings only shows the built in gpu

In xorg.conf I see both the internal and external gpus listed (Device0 and Device1) I also see Monitor0 and 1 and Screen0 and 1.

If I boot up Win10 on it, everything just works.

Really has me stumped. Any idea what I might have wrong?

Thanks!

Could you please double check the following settings.

Is “Direct Access” enabled for you? You can find it under “Gnome-settings” > “Devices” > “Thunderbolt”

Are the new monitors enabled?

Hi,

Yes, Direct Access is on and the thunderbolt device is authorized. The NVidia driver sees the GPU (as indicated by running nvidia-smi).

The monitor attached to the GPU does not show up in display settings. Only the laptops built in monitor does.

I typically don’t use Gnome (prefer Cinnamon). But I have ran Gnome with both Wayland and XOrg. XOrg is supposed to support ExternalGPUs if Option “AllowExternalGpus” “True” is present in the Screen config.

Do you know if Wayland supports multiple GPUs rendering at the same time? I remember reading somewhere that it doesn’t.

I found this thread on reddit: https://www.reddit.com/r/archlinux/comments/b77ic1/external_display_wayland_intelnvidia/

It seems the issue is hard-wired.

Our friends at Arch Linux might be able to help: https://wiki.archlinux.org/index.php/bumblebee#Output_wired_to_the_NVIDIA_chip

I hope this helps! :slight_smile:

Thanks,

I have had some limited (very limited) success. If I run Gnome under XOrg instead of Wayland, I have been able to end up with two X Screens. However, the desktop manager (whether it be Gnome/Cinnamon, etc) will only render to Screen0. My mouse will travel to the eGPU screen, but changes to the default ‘X’ cursor. No windows can be dragged to it, etc.

This all tells me that at the hardware / driver level that things are working. I’ll keep messing around with it as time permits and update this thread as I figure out more.