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I am running openSUSE Leap 15.1 on my Lenovo ThinkPad T440p laptop and use the Dell 24' monitor E248WFP as an external second display.
At times the external display goes blank and shows "Entering Power Save".
The laptop display is not effected.
I still could not pinpoint what triggers this behaviour.
It try the usual things "restart", "shutdown", "disconnecting the monitor"
and after a while, sometimes hours, the screen comes to live again.
I checked dmesg, but was not sure what to look for.
I also saved /etc/interrupts and compared it to the file after the display
went blank with the result:
* there was an IO-APIC 9-fastevi interrupt
* there were 2333 new interrupts listed in the line with PCI-MSI
* there were 10449 new interrupts in the line TLB shootdown
I do not want to put anybody on a possible false track, I am just telling
what I have done so far.
I would appreciate any help
* in finding out what goes wrong
* and come up with a solution for avoiding this inconvenience or
at least recover faster from it.
Simply running xrandr will report the names of the connected outputs and the screen ID. --display takes the screen ID. --output takes a connector name.
Quote:
I installed inxi.
It was a bit tricky to find out that I had to install
in addition also Mesa-demo-x
Entering the command inxi -GxxSza yields:
Code:
inxi -GxxSza
/usr/bin/inxi: illegal option -- a
That's a result of using the antique inxi rpm from 15.1, and why I provided the URL to the current version. If you consult its man page you'll see it has an updates switch -U. It should also explain how to make it work.
a produces the line that's missing from the antique.
man xrandr might have something to apply to the external output to wake it back up, maybe --auto. How to keep it active is another question. https://www.kernel.org/doc/Documenta...parameters.txt has some cmdline options that can affect video behavior, e.g. acpi_backlight= or consoleblank=.
good point!
What I did not mention in my first post: I had connected the Dell monitor
to a second laptop running kubuntu as OS and everything work without a hitch.
But, since I still do not know what triggers the entering into power save this was not
finally conclusive. Maybe, if I had worked with that laptop a little long the effect
might have happened.
So, I checked today the OSD menue of the Dell monitor. It offers no item on power saving.
Last edited by pschmitt; 12-11-2019 at 11:57 AM.
Reason: last remark was nonsense
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