Second monitor not displaying w/ HMDI-DVI adapter

[kooloo_kooloo]

Hello all,

I have encountered some issue trying to use an external monitor (early 2000s LG Flatron) with my laptop (Framework 13) running Debian 12. While the hardware appears to be detected correctly, as shown by running xrandr on the terminal, it displays nothing but a "Check cables connection" error message, before going into idle.

The signal goes from the laptop's HDMI output through an HDMI to DVI adapter, before going into the monitor. The adapter is passive, and has shown to transmit a signal sent from the graphics card of a Windows machine without any issue, using the same adapter setup. Note that I have successfully been using an external monitor with my Linux machine, although with a more straightforward HDMI setup. The only hurdle I could mention is that, on occasions, the HDMI-connected monitor doesn't display if not plugged in before boot. Knowing this did not change anything regarding the DVI-connected monitor.

I will be happy to run any update and test you might suggest, although I am still a beginner with Debian 12. If you think this might be unrelated to the distro, please say so. I will ask the people over on the Framework forum.

Thank you very much.

[mrmazda]

The way you've written it's not entirely clear which connector is on the computer, and which on the display. IME, DVI from computer to HDMI into display is highly reliable. I can't remember how long ago I even tried the other direction.

Can you try that LG with something other than your laptop, to be sure it works through the needed input?

Does LG autosense input, or require manual switching for appropriate input selection?

Is the behavior any different when on a VT instead of X?

Are the native aspect ratios of LG and laptop the same?

What does Xorg.0.log in /var/log/ or ~/.local/share/xorg/ report, or Wayland equivalent in journal - any clues there?

What GPU is in that laptop? Is it running on a KMS driver? If not, meaning X is running on a fallback VESA or FBDEV X driver, as when kernel cmdline contains nomodeset or radeon.modeset=0, or no X at all, there is no support for more than one display at a time.

Please show output here, using code tags, from inxi -GSaz --vs, so that we can see what's in that laptop.

[kooloo_kooloo]

Thanks for your reply.

To be extra clear, my laptop has no DVI output, only HDMI, while the Flatron monitor only has DVI and VGA inputs, hence the need for an adapter. The computer is outputting HDMI, and the display is inputting DVI, not the other way around.

Can you try that LG with something other than your laptop, to be sure it works through the needed input?

This setup (HDMI to DVI) ran correctly on a tower PC running Windows 10. The signal was outputted from a dedicated Nvidia graphics card.

Does LG autosense input, or require manual switching for appropriate input selection?

The LG autosenses the input.

Does the behavior any different when on a VT instead of X?

Sorry, I am not familiar with what "x" and "vt" stand for in this scenario. Could you specify?

Are the native aspect ratios of LG and laptop the same?

The native aspect ratios aren't the same (Integrated display=2256x1504 vs Ext. monitor=1280x1024). Over on the Gnome display settings, it does detect the LG's exact resolution. I have previously encountered no issues running an external monitor w/ differing resolution using this laptop.

I ran journalctl to get some logs for my current session, the external display plugged in and everything. These are the lines :

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sep 05 08:14:33 boby-lapointe gnome-shell[1143]: Running GNOME Shell (using mutter 43.8) as a Wayland display server
sep 05 08:14:34 boby-lapointe gnome-shell[1143]: Using Wayland display name 'wayland-0'
sep 05 08:15:00 boby-lapointe systemd[1699]: Starting org.gnome.Shell@wayland.service - GNOME Shell on Wayland...
sep 05 08:15:00 boby-lapointe systemd[1699]: Condition check resulted in org.gnome.Shell@wayland.service - GNOME Shell on Wayland being skipped.
sep 05 08:18:37 boby-lapointe gnome-shell[4672]: Running GNOME Shell (using mutter 43.8) as a Wayland display server
sep 05 08:18:38 boby-lapointe gnome-shell[4672]: Using Wayland display name 'wayland-0'
sep 05 08:21:02 boby-lapointe gnome-shell[1133]: Running GNOME Shell (using mutter 43.8) as a Wayland display server
sep 05 08:21:02 boby-lapointe gnome-shell[1133]: Using Wayland display name 'wayland-0'
sep 05 08:21:14 boby-lapointe systemd[1685]: Reached target gnome-session-wayland.target - GNOME Wayland Session.
sep 05 08:21:14 boby-lapointe systemd[1685]: Starting org.gnome.Shell@wayland.service - GNOME Shell on Wayland...
sep 05 08:21:14 boby-lapointe gnome-shell[1849]: Running GNOME Shell (using mutter 43.8) as a Wayland display server
sep 05 08:21:14 boby-lapointe gnome-shell[1849]: Using Wayland display name 'wayland-0'
sep 05 08:21:15 boby-lapointe systemd[1685]: Started org.gnome.Shell@wayland.service - GNOME Shell on Wayland.
sep 05 08:21:15 boby-lapointe systemd[1685]: Reached target gnome-session-wayland@gnome.target - GNOME Wayland Session (session: gnome).

I am only familiar with Wayland.

What GPU is in that laptop?...

The laptop has no dedicated GPU. It uses the integrated graphics of the AMD Ryzen 5 7640U, which are Radeon 760M. Given the youth of that hardware, and the fact that I was able to run more than one display previously, I assume it has KMS enabled and is running on its driver.

Note that I have manually updated all initramfs back in May, regarding another issue.

Please show output here, using code tags, from inxi -GSaz --vs

Code: Select all

System:
  Kernel: 6.1.0-22-amd64 arch: x86_64 bits: 64 compiler: gcc v: 12.2.0
    parameters: BOOT_IMAGE=/boot/vmlinuz-6.1.0-22-amd64
    root=UUID=42c5668e-4429-4001-83e1-1ce2c2e3e1bb ro quiet
  Desktop: GNOME v: 43.9 tk: GTK v: 3.24.38 wm: gnome-shell dm: GDM3 v: 43.0
    Distro: Debian GNU/Linux 12 (bookworm)
Graphics:
  Device-1: AMD Phoenix1 vendor: Framework driver: amdgpu v: kernel
    arch: RDNA-3 code: Phoenix process: TSMC n4 (4nm) built: 2022+ pcie: gen: 4
    speed: 16 GT/s lanes: 16 ports: active: DP-4,eDP-1 empty: DP-1, DP-2,
    DP-3, DP-5, DP-6, DP-7, DP-8 bus-ID: c1:00.0 chip-ID: 1002:15bf
    class-ID: 0300 temp: 38.0 C
  Device-2: Realtek Laptop Camera type: USB driver: uvcvideo bus-ID: 3-1:2
    chip-ID: 0bda:5634 class-ID: 0e02 serial: <filter>
  Display: wayland server: X.org v: 1.21.1.7 with: Xwayland v: 22.1.9
    compositor: gnome-shell driver: X: loaded: amdgpu
    unloaded: fbdev,modesetting,radeon,vesa dri: radeonsi gpu: amdgpu
    display-ID: 0
  Monitor-1: DP-4 model: LG (GoldStar) L1933TR serial: <filter> built: 2007
    res: 1280x1024 dpi: 86 gamma: 1.2 size: 376x301mm (14.8x11.85")
    diag: 482mm (19") ratio: 5:4 modes: max: 1280x1024 min: 720x400
  Monitor-2: eDP-1 model: BOE Display 0x0bca built: 2022 res: 2256x1504
    dpi: 201 gamma: 1.2 size: 285x190mm (11.22x7.48") diag: 343mm (13.5")
    ratio: 3:2 modes: max: 2256x1504 min: 640x480
  API: OpenGL v: 4.6 Mesa 22.3.6 renderer: AMD Radeon Graphics (gfx1103_r1
    LLVM 15.0.6 DRM 3.49 6.1.0-22-amd64) direct-render: Yes

[mrmazda]

Does LG autosense input, or require manual switching for appropriate input selection?

The LG autosenses the input.

If it can be switched manually it could be worth trying.

Does the behavior any different when on a VT instead of X?

Sorry, I am not familiar with what "x" and "vt" stand for in this scenario. Could you specify?

X means either Xorg or Wayland, GUI operation. The linux kernel provides text mode Virtual Terminals reachable by using Ctrl+Alt+ one of several of the function keys. Usually F4-F6 can be counted upon. Ctrl-Alt-F4 while running a Gnome session should produce a text mode shell prompt on a black screen. Alt-F1 or Alt-F2 or Alt-F7 or possibly others should return you to Gnome.

Are the native aspect ratios of LG and laptop the same?

The native aspect ratios aren't the same (Integrated display=2256x1504 vs Ext. monitor=1280x1024). Over on the Gnome display settings, it does detect the LG's exact resolution. I have previously encountered no issues running an external monitor w/ differing resolution using this laptop.

1.5:1 vs 1.33:1. I've encountered displays that with multiple display configurations simply won't accept apparently appropriate signals. Possibly this issue could be overcome using a config file in /etc/X11/xorg.conf.d/, an optional directory that may need to be created in order to make use of it. Output from xrandr might be of use deciding whether to pursue this direction.

I ran journalctl to get some logs for my current session, the external display plugged in and everything. These are the lines :
..
I am only familiar with Wayland.

Have you thought to try your other Gnome option, Xorg instead of Wayland? Could be you're up against a Wayland bug. If you're not using auto-login, you should be able to switch type at your GDM login screen. If you are, log out instead of shutdown or reboot to reach it and switch. The GDM screen may provide a session type alternative to Gnome. If it does, try that too.

inxi -GSaz --vs

...
Distro: Debian GNU/Linux 12 (bookworm)
...

It looks like you used the ancient broken inxi provided by Bookworm, because what you provided is not from inxi -GSaz --vs as requested. If you edit /etc/inxi.conf to remove the built in updater blocker, sudo inxi -U will update it to current version, 3.3.36. --vs reports the inxi version. Knowing the version can help to understand and/or interpret its output, which is known to change among versions.

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> inxi --vs
inxi 3.3.36-00 (2024-09-04)
>