Whenever I boot without an external monitor enabled then I get problems trying to enable my u2868pqu monitor with hindsight. Xorg will recognize and it will let me configure the external monitor. However the external monitor will stay black and without a signal in spite of being configured well. If I just reboot the X-server with the monitor cable unplugged then there will be no problem in enabling my u2868pqu monitor. Consequently I would assume this to be a kernel / nouveau module bug since it depends on boot time not on the time when I start the X-server. Is there any way to post the external monitor if I have booted without it? What would you believe is going wrong here with nouveau and the HDMI port?
Created attachment 195641 [details] journalctl -b / messages
Created attachment 195651 [details] journalctl since s2ram: external monitor does not awake Same problem as soon as I send my machine into s2ram: The external monitor stays dark 'no signal' afterwards.
s2ram; new test results: * when booted with nouveau.modeset=0 the external monitor is not enabled at all (i.e. definitely a bug related to the nouveau kernel module). * suspecting this to be backlight issue I have tried to boot into runlevel 1 with the following kernel parameters the nouveau module being loaded - video.use_bios_initial_backlight=0 - video.use_native_backlight=1 - acpi_osi= Unfortunately none of the above kernel command line parameters did yield any difference with respect to s2ram: the external monitor always got disabled by suspend.
Now I have tested it with the proprietary Nvidia 340.xx driver: s2ram works flawlessly with the proprietary driver the external monitor getting re-enabled normally. However the non-oss driver runs unstable on my machine and is not an option. The bug is apparently a driver issue and not a firmware/acpi problem.
Created attachment 197481 [details] clean journal under runlevel 1 with s2ram at last Would anyone mind to have a look at the logs or propose any further actions?
It is really a pity that my NVIDIA Corporation G96M [GeForce 9600M GT] has been crossed out of the list of supported cards since an update to kernel 4.3.3-2. It has worked well with the nouveau driver except for this bug. Latest tests have shown that the monitor can now be enabled with hindsight after booting; however the monitor being disabled by s2ram is a problem that has persisted up to now.
Comment #6 is now resolved: Please excuse the panic; I think that there was just a temporary configuration issue with Arch Linux (see also: https://bugs.freedesktop.org/show_bug.cgi?id=93405); i.e. /dev/card0 needs some time to appear; now let us go on with the s2ram issue as the issue with enabling the monitor after boot is already resolved!
... and now the external monitor stays black all the time no matter what I do with xrandr/nouveau while the proprietary driver does happily continue to work. It is a shame that nobody seems to care about this bug! Shall I trash this notebook because of a driver issue?
... gonna try it with kernel 4.4 now as I heard that there were certain improvements ...
As you've probably noticed, no one from the nouveau team really looks at this bug tracker. (I happened to notice this one because it's a slow day on the dri-devel list.) I recommend filing bugs on bugs.freedesktop.org xorg -> Driver/nouveau if you'd like the attention of the nouveau developers.
bug has now been moved to freedesktop.org: https://bugs.freedesktop.org/show_bug.cgi?id=93887