Dual EVGA 1070s, three monitors on Debian: xrandr: Configure crtc 4 failed

Hello All! I am attempting to get a dual 1070 setup working on Debian 11.

lspci | grep NVIDIA
01:00.0 VGA compatible controller: NVIDIA Corporation GP104 [GeForce GTX 1070] (rev a1)
01:00.1 Audio device: NVIDIA Corporation GP104 High Definition Audio Controller (rev a1)
09:00.0 VGA compatible controller: NVIDIA Corporation GP104 [GeForce GTX 1070] (rev a1)
09:00.1 Audio device: NVIDIA Corporation GP104 High Definition Audio Controller (rev a1)

Debian seems to detect both GPU’s just fine. 01:00.0 is powering a DVI monitor, while 09:00.0 is powering a DVI and a HDMI. While Xinerama is on, I can get all three monitors to come up and work as a single, large desktop. I am attempting to have three separate desktops with 01:00.0 being the primary. I can make both screens on 09:00.0 turn on if I configure X11 with nvidia-settings as root and add them as separate X screens, however, the mouse is the only thing that is displayed over a black screen. I’m not sure what else to do as I have poked around in xorg.conf, changed the MultiGPU setting, tried different settings regarding the Screens, Monitors, etc. with no change no matter what was configured.

I attempted to place just this config in the xorg.conf as described here and was able to find them in Displays, but when I attempt to enable them, they remain off.

Section "Device"
  Identifier "nvidia"
  Driver "nvidia"
  BusID "PCI:1:0:0"
  Option "PrimaryGpu" "yes"
EndSection

Once I’ve rebooted, I attempted to run:


Providers: number : 2
Provider 0: id: 0x1b8 cap: 0x1, Source Output crtcs: 4 outputs: 8 associated providers: 1 name:NVIDIA-0
Provider 1: id: 0x373 cap: 0x2, Sink Output crtcs: 4 outputs: 8 associated providers: 1 name:NVIDIA-G0

Then attempt this command as described in the post:

xrandr --setprovideroutputsource NVIDIA-G0 NVIDIA-0 && xrandr --auto

I receive this error:

xrandr: Configure crtc 4 failed

And even though I have three monitors hooked up xrandr is still only detecting a single one my primary GPU:


Monitors: 1
 0: +*DVI-D-0 1920/531x1080/298+0+0  DVI-D-0

Googled around a bit but I havent found anything anywhere that seems to point me in the right direction so I figured why not start here. I have attached a nvidia-bug-report to this post as well. Thank you in advance!

nvidia-bug-report.log.gz (474.8 KB)

Please set kernel parameter
nvidia-drm.modeset=1

Hi generix! Thank you for the reply. I set the parameter in /etc/default/grub:

GRUB_DEFAULT="0"
GRUB_TIMEOUT="5"
GRUB_DISTRIBUTOR="`lsb_release -i -s 2> /dev/null || echo Debian`"
GRUB_CMDLINE_LINUX_DEFAULT="quiet"
GRUB_CMDLINE_LINUX="nvidia-drm.modeset=1"

Rebuilt grub:

grub-mkconfig -o /boot/grub/grub.cfg
sudo update-grub

And then rebooted. Unfortunately, there was no change. I have moved one of the monitors from the secondary card to the primary card and am able to configure it within Displays/see it in xrandr --listmonitors:

# sudo xrandr --listmonitors
Monitors: 2
 0: +*DVI-D-0 1920/531x1080/299+0+0  DVI-D-0
 1: +HDMI-0 1920/477x1080/268+1920+0  HDMI-0

Thank you for the assistance and I will continue to poke around a bit more. Perhaps I’ve missed something somewhere else?

About separate desktops, see this:
https://forums.developer.nvidia.com/t/problem-installing-nvidia-driver-on-red-hat-8-4/195163/9?u=generix