DevHeads.net

Notebook won't configure plug-in monitor

My Asus N75SF recognizes that a monitor (HDMI TV) was plugged, but it
fires off 4-8 copies of the Display configuration app, none of which
recognize that monitor.

I haven't tried booting with the HDMI TV plugged in yet, but I'm
wondering if it might be a hardware issue. I didn't see anything in
the BIOS that might be related.

I did try to reset the autoconfigure box of the Display config app -
no difference.

Any clues where to look?

Thanks.
MR

Comments

Re: Notebook won't configure plug-in monitor

By Xen at 06/07/2017 - 03:52

MR ZenWiz schreef op 07-06-2017 9:11:
I know it isn't much of a solution, but try to use the "xrandr" tool.

In general xrandr without parameters should show you the list of
outputs, both connected and unconnected.

Then, to my conception,

xrandr --ouput <internal one> --primary --output HDMI-0 (for example)
--clone

should give you a clone of your primary output (the notebook screen) on
your secondary output.

You can set the resolution with --mode, such as --mode 1920x1080.

Scaling is also possible, but a bit too hard to relate from memory.

I have a script for Kubuntu (which is the same, xrandr is not KDE
specific) that would trigger based on udev activation (monitor changes
cause a udev event that you can install a trigger for in /etc/udev) that
(for my own computer) creates a scaled duplicate of the primary display.

Scaling can be unpleasant depending on resolutions!!!

The display is not rendered twice, but the primary display is scaled
onto the other display.

So my script will:

- check the list of outputs
- decide which ones are connected
- if there is an AV receiver attached but not a monitor, notice the
difference
- if only the TV is turned on, make it primary
- if only the monitor is turned on, make it primary
- if both are turned on, make the monitor primary and the TV secondary

- in that case, scale the primary in such a way as to (manual pick) get
the best looking image on the other-resolution display.

In my case I have to scale from 16:10 (1440x900) to 16:9 (1920x1080 or
1360x768) and for my case I picked the latter.

I did post something about it on KDE forums:

<a href="https://forum.kde.org/viewtopic.php?f=66&amp;t=136696" title="https://forum.kde.org/viewtopic.php?f=66&amp;t=136696">https://forum.kde.org/viewtopic.php?f=66&amp;t=136696</a>

But maybe this is a simpler solution to start out with:

<a href="https://forum.kde.org/viewtopic.php?f=14&amp;t=88659#p248310" title="https://forum.kde.org/viewtopic.php?f=14&amp;t=88659#p248310">https://forum.kde.org/viewtopic.php?f=14&amp;t=88659#p248310</a>

Note that I had a race condition with KScreen (that tries to do the same
thing) so I created a rather convoluted way of waiting till KScreen was
finished by reading journalctl logs :p.

When all else failed, I would run (in KDE) "alt+space, fixscreen".

And my proper configuration and display would pop up :p.

I probably have a newer version on my system but I have to reboot to get
it :p.