Arch Linux

GMON

Member

Registered: 2021-12-19

Posts: 14

What is my output-name in order to use Nvidia Prime synchronisation?

Im trying to enable prime synchronization with the help of the arch wiki:
https://wiki.archlinux.org/title/PRIME# … ronization

i have...

nvidia-drm.modeset=1

...as a kernel parameter

And now should be able to enable it with:

xrandr --output <output-name> --set "PRIME Synchronization" 1

However, could not figure out what"<output-name>" should be replaced with on my system.

My first though would have been "eDP-1", thats my laptop monitor, but that did not work.

Here is my xrandr --current output with no monitors (besides the built in one) active/attached:

Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 16384 x 16384
eDP-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 194mm
   1920x1080     60.00*+  59.97    59.96    59.93  
   1680x1050     59.95    59.88  
   1400x1050     59.98  
   1600x900      59.99    59.94    59.95    59.82  
   1280x1024     60.02  
   1400x900      59.96    59.88  
   1280x960      60.00  
   1440x810      60.00    59.97  
   1368x768      59.88    59.85  
   1280x800      59.99    59.97    59.81    59.91  
   1280x720      60.00    59.99    59.86    59.74  
   1024x768      60.04    60.00  
   960x720       60.00  
   928x696       60.05  
   896x672       60.01  
   1024x576      59.95    59.96    59.90    59.82  
   960x600       59.93    60.00  
   960x540       59.96    59.99    59.63    59.82  
   800x600       60.00    60.32    56.25  
   840x525       60.01    59.88  
   864x486       59.92    59.57  
   700x525       59.98  
   800x450       59.95    59.82  
   640x512       60.02  
   700x450       59.96    59.88  
   640x480       60.00    59.94  
   720x405       59.51    58.99  
   684x384       59.88    59.85  
   640x400       59.88    59.98  
   640x360       59.86    59.83    59.84    59.32  
   512x384       60.00  
   512x288       60.00    59.92  
   480x270       59.63    59.82  
   400x300       60.32    56.34  
   432x243       59.92    59.57  
   320x240       60.05  
   360x202       59.51    59.13  
   320x180       59.84    59.32  
DP-1 disconnected (normal left inverted right x axis y axis)
HDMI-1 disconnected (normal left inverted right x axis y axis)
DP-2 disconnected (normal left inverted right x axis y axis)
HDMI-2 disconnected (normal left inverted right x axis y axis)

as well as some specs:

root@GMON
---------
OS: Arch Linux x86_64
Host: 81NX Lenovo Yoga S740-15IRH
Kernel: 5.16.10-arch1-1
Uptime: 2 hours, 11 mins
Packages: 1810 (pacman), 13 (flatpak)
Resolution: 1920x1080
WM: i3
Terminal: alacritty
CPU: Intel i7-9750H (12) @ 4.500GHz
GPU: NVIDIA GeForce GTX 1650 Mobile / Max-Q
GPU: Intel CoffeeLake-H GT2 [UHD Graphics 630]
Memory: 3087MiB / 15717MiB

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 25,210

Re: What is my output-name in order to use Nvidia Prime synchronisation?

It should be enabled by default in most cases, potential bugs in any of the current versions non-withstanding, the "output" is whatever your screen is eventually connected to. What's your general Optimus/PRIME configuration here? If you didn't set up anything in particular then your laptop monitor will always just be driven by the integrated GPU and PRIME sync considerations only relevant when explicitly invoking the dGPU via prime-run or similar.

GMON

Member

Registered: 2021-12-19

Posts: 14

Re: What is my output-name in order to use Nvidia Prime synchronisation?

You're on point. I use the integrated intel graphics for normal work to save battery life prime-run for more demanding applications.

I havent tinkered with the prime configurations, prime-run worked out of the box and the only issue im having is screen tear when using the nvidia card through prime-run.

I did change some configs for my intel card because it had screen tear issues as well.

My config file under "/etc/X11/xorg.conf.d/20-intel.conf"

Section "Device"
  Identifier "Intel Graphics"
  Driver "intel"
  Option "TearFree" "true"
EndSection

This shouldnt cause any issues with prime afaik.

"output" is whatever your screen is eventually connected to

I assumed that was "eDP-1". To be clear here is what i ran and what error message i got:

xrandr --output eDP-1 --set "PRIME Synchronization" 1

 X Error of failed request:  BadName (named color or font does not exist)
  Major opcode of failed request:  140 (RANDR)
  Minor opcode of failed request:  11 (RRQueryOutputProperty)
  Serial number of failed request:  36
  Current serial number in output stream:  36

The wiki didnt detail what exactly was meant to be inplace of <output-name> , neither did searches on duckduckgo, reddit and on this forum.

Last edited by GMON (2022-02-25 17:22:03)

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 25,210

Re: What is my output-name in order to use Nvidia Prime synchronisation?

Remove that config file and xf86-video-intel. PRIME sync support is afaik only officially implemented in conjunction with the modesetting driver, which is any case better tested with PRIME and generally has less bugs than the intel xorg ddx. If you have tearing with just the modesetting driver, consider using a compositor to help with tearing like picom is a popular standalone choice.

FWIW to check whether you even have the PRIME property (... again it's somewhat normal and expected this won't show up on an output that's technically purely driven by the integrated card) what's your output of

xrandr --verbose

Last edited by V1del (2022-02-26 13:50:15)