From: nospam@needed.invalid   
      
   On Sun, 9/28/2025 7:39 AM, pinnerite wrote:   
   > On Thu, 25 Sep 2025 22:14:14 +0100   
   > pinnerite  wrote:   
   >   
   >> This morning my main computer (this one) came up but only one screen   
   >> was working.   
   >>   
   >> The graphics card has 4 sockets. One HDMI and 3 DisplayPorts. Both my   
   >> screens use HDMI, so they have adapters. I switched everything round   
   >> and found both screens worked provided they were plugged into one   
   >> particular displayport.   
   >>   
   >> Checking "Display" in system settings only shows one screen.   
   >>   
   >> Just before I clocked off for the night, I thought I would boot up on   
   >> the Mint 22.1 install flashdrive.   
   >>   
   >> To my surprise, delight and consternation both screens came up.   
   >>   
   >> Now I need to work out where the fault lies in the software?   
   >>   
   >> Suggestions please. :(   
   >>   
   >> Alan   
   >>   
   >   
   > By switching to the instllation kernel 6.8.8-51, the problem disappeared!   
   >   
   > Alan   
      
   When you were on 6.8.0-84, did you check /var/log/gpu-manager.log for details ?   
      
   Compare to what the /var/log/gpu-manager.log for your 6.8.0-51 run generates.   
   When the two monitors are working, it won't show in --list-monitors as None-1   
   any more. If should be using the actual video card output type names,   
   such as HDMI, DP, VGA. The number after the name, is used in cases where the   
   card has three DP as in DP-1, DP-2, DP-3.   
      
   If you want to file a bug report, from the safety of your 6.8.0-51 alternate   
   selection, you might want to examine the contents of that file, because   
   as far as I know, that might have the info needed to add "content" to a   
   bug report. I don't think necessarily, the output of "dmesg" would contain   
   the smoking-gun for a monitor-not-detected problem. It's more than just   
   monitor-not-detected, because your single monitor in the non-working case   
   was listing the monitor as "None-1" and not "HDMI-1" as it is supposed   
   to be. Even your case of getting one monitor running, the driver   
   was not likely loaded. If you check your INXI in the two cases, you   
   may see a different declaration of "loaded" and "unloaded" stuff.   
      
   If X11 (on top of XWayland) is initializing, there would be an X11 log   
   file as well. But it may not be naming the details of the physical card,   
   as it would be getting some sort of info from Wayland rather than   
   from the hardware, when it runs on top of XWayland. The Linux layer cake   
   is a lot taller now that it is filled with foolishness. This is why   
   stuff breaks.   
      
   You would also want to mention in a report, whether you were Secure Booting   
   or not, whether in UEFI or Legacy BIOS (CSM) mode and so on. As I think   
   the higher bar of Secure Boot, it might require that the GOP graphics   
   driver be signed somehow. Maybe a UEFI/TPM attestation failure could break   
   it...   
   I don't know how that works. Someone made the claim on Windows the   
   other day, that something unsigned on their NIC, caused the secure boot   
   to turn off their network, which does not sound plausible. Secure boot   
   should just blow up the boot entirely, if it is not happy.   
      
      Paul   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)