Nvidia PCIE Card and iGPU on CPU used together

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Moved from here:

Hi! Just a very, very new user chiming in here!

I had a similar problem over the last few days, though I’m on a desktop, not a laptop.

My system was hanging when starting up:

  • black screen on both monitors
  • then GRUB MENU (without any actual menu options) on monitor-0 and
  • the usual POST-like info on monitor-1 (not sure if that’s actually POST output; I’m very new to linux outside of a PuTTY terminal and WSL)
  • Then a single cursor underline on monitor-1, and a weird glitchy line under GRUB MENU on monitor-0.
  • This would hang again for long enough to make me feel like it was going to freeze there
  • but then monitor-0 would smarten up and I’d get the log-in screen.

The single cursor underline persisted on monitor-1 though and xrandr wasn’t recognizing monitor-1 at all.

I tried a bunch of troubleshooting from various sources, spent a whole day reading all kinds of forums, nvidia docs, X11 docs, intel docs, etc. but found no one with exactly the same situation and no solutions. I scoured my whole file system and read every log & config file that looked like it might have anything to do with GPU/displays/monitors/whatever.

I finally settled on trying a bunch of frankenstein xorg .config files, pieced together to resemble a few examples from Arch wiki and nvidia docs related to somewhat similar scenarios.

BUT before copying them all into the proper directory, I made a copy of /etc/X11/xorg.conf.d/20-nvidia.conf and removed the original, then rebooted.

Lo and behold, monitor-1 suddenly worked! Everything seems okay now (I think).

So, getting rid of /etc/X11/xorg.conf.d/20-nvidia.conf was all I had to do, it seems.
Learned a lot along the way at least!


I think probably because you have multi monitor otherwise it probably wouldn’t have affected it. But i think this file isn’t needed and is causing some issues. Glad you were able to resolve it.

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It would be really interesting to see a boot log and xorg log on such system with the xorg nvidia config file present :wink:
This would show us what exactly is wrong with it…
The only thing i can see is that your system @reclusiveAlgorithm is noit an optimus notebook but a Desktop system with a PCIE Nvidia Card and an integrated iGPU that comes with the CPU…
Usually these are not connected like on optimus systems, and they should not interfere with each other.
What would be also interesting is to check if you have any settings for the iGPU handling in Bios/Firmware.
And if you have a Display connected to the integrated GPU or only to the Nvidia Card.

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Yes, that’s what I thought too! Before attempting the install, I read about a lot of folks having trouble with this on notebooks but I didn’t come across anything about trouble on a desktop.

I did a few live boots from USB first to check things out and both monitors worked each time. No issues. I really expected a smooth install.

Once I finished the install and realized my second monitor was not showing up, I tried each of the different iGPU settings in Bios. When I installed, Bios was auto selecting GPU. I rebooted with the intel card as the default (not sure if that completely disables the nvidia card or not) and then had no monitors at all once the POST messages were finished; the monitor connected to the nvidia card went into sleep mode. Rebooted again with nvidia card selected as the default and again had no monitors at all. I don’t remember if either monitor went to sleep at that point, this was one of the first things I tried and a lot has happened since then, haha. I changed the Bios back to auto, so that’s what it should be on now.

I do have one monitor connected to the nvidia card, the other connected to iGPU. And this is because I only have HDMI cables on hand; nvidia card has one HDMI port, one DisplayPort. Same for the iGPU. I think there’s a DVI back there somewhere too but again, I only had HDMI cables.

I am curious whether having both monitors connected to the same device would have made a difference. Picking up a DisplayPort cable was on my list of things to try but it’s been between -30°C and -40°C the last few days so I was extra motivated to figure it out without leaving the house :upside_down_face:

I still have the xorg nvidia config file. I will put it back where it wants to belong and try booting up again to get the boot log and the xorg log.

One question: I know the xorg log is /var/log/Xorg.0.log but please let me know what you’d like to see for the boot log. Is that journalctl -b ?

I’m still a complete newbie and I’ve read so many logs and configs recently, I don’t want to give you the wrong thing :innocent:

Okay, I put /etc/X11/xorg.conf.d/20-nvidia.conf back.

Same result as before, just a black screen with only the cursor on the monitor that’s connected to iGPU.

Here are the logs:

Not sure if it’s necessary or if it helps, but I included hwinfo --short which still lists both monitors and both graphics cards.
xrandr -q only shows the one monitor again.

Hope that helps and let me know if there’s anything else that might be useful!

it was not clear before that you try to use both cards.
And it is logical that if there is only a conf for the Nvidia Card it will not setup the display plugged to intel card.
If no conf is present it uses auto-configuration, which can work for you or not … and in your case it seems to work.

That definitely makes sense.

Are there any potential negatives for having a set-up without the config files?

It does seem to work fine, and I am happy with leaving “well-enough” alone, but I haven’t really done much yet beyond getting the system set-up and tweaking appearances to my liking. But if I were to run any GPU intensive programs, am I better off being more explicit with the configuration?