Le mercredi 03 novembre 2021 à 10:56 +0000, Simon McVittie a écrit : > Control: tags -1 + moreinfo > > On Wed, 03 Nov 2021 at 09:55:20 +0100, Julien Puydt wrote: > > Where should I have a look to find error messages and fix the issue? > > If in doubt, the answer is always the systemd journal (system log). >
Which I don't know how to read ; I get a lot of: DMAR: DRHD: handling fault status reg 3 DMAR: [DMA Read NO_PASID] Request device [0x01:0x00.0] fault addr 0xfb808000 [fault reason 0x06] PTE Read access is not set and: dmar_fault: 36986 callbacks suppressed which might be a smoking gun... > > (1) The main "card" is Intel Corporation CoffeeLake-H GT2 [UHD > > Graphics > > 630], with kernel module i915. The second "card" is NVIDIA > > Corporation > > GP107M [GeForce GTX 1050 Mobile], with kernel module nouveau. > > This sounds like it might be a dual-GPU laptop. Am I correct? If yes, > what model of laptop? > Yes, it's a laptop, ACER Nitro AN515-52. > How is the "first" screen with correct display > connected? (HDMI? DisplayPort? VGA? Built-in screen of a laptop?) > Built-in screen. > How is the "second" screen with incorrect display connected? > HDMI cable. > Do you know which GPU the two screens are physically connected to? > For a desktop, it should be obvious from looking at which part they > are > plugged into; for a laptop, it's non-obvious, but we might be able to > find > out if you told us what laptop it is. > The built-in screen is i915 and the external nouveau, as far as I know -- at least I always had to modprobe nouveau for the second screen to activate. > > (2) I think both physical screens are detected, since xrandr says: > > > > Screen 0: minimum 16 x 16, current 3840 x 1080, maximum 32767 x > > 32767 > > XWAYLAND0 connected primary 1920x1080+0+0 (normal left inverted > > right x > > axis y axis) 340mm x 190mm > > 1920x1080 60.05*+ > > XWAYLAND1 connected 1920x1080+1920+0 (normal left inverted right x > > axis > > y axis) 530mm x 300mm > > 1920x1080 143.88*+ > > This is telling you about the emulated screens corresponding to your > real screens, as presented by Xwayland based on information provided > by GNOME Shell in native Wayland mode. For the real (lower-level) > story, it might be helpful to look at: > > head /sys/class/drm/card*-*/status > head /sys/class/drm/card*-*/modes > Status is "connected" for both ; for modes card0-eDP-1 has a single one and the card1-HDMI-A-1 has many. > I wonder whether the very high refresh rate (144 Hz) on the second > screen is relevant to this: that's relatively unusual. If you > configure it for a lower refresh rate like 60 Hz in gnome-control- > center, does that work any better? I had to install gnome-control-center for that ; no, it doesn't work any better. Thanks, J.Puydt
