Cannot get ubuntu to display on LG tv

[glubbish]

This is a problem a friend of mine has, he knows even less ubuntu than I do.
But I did the original install for him and tried to boot ubuntu via usb.
It may take variable amounts of time to get requested info.

I have tried ctlr/alt f1 etc but could not get a prompt, still just the blank screen.

I found the inputs on the LG tv somewhat mystifying. They appear to be set up for specific devices.
However, I believe that part is setup correctly as the windows boot works fine (same NUC, avr, tv etc).

I will try "Disable Intel iGD in the BIOS." from the link above. It may be a LG specific issue, that the samsung does not have.
I will get him to check /ect/fstab to check if it was I eufi install (I can't remember, but its likely).

[vidtek]

Glubbish-

You need to use the LG remote control, in the menus you will find a setting for display modes on the various inputs.

The auto setting only works for Windows now, you will have to play around with the settings of the TV when in Ubuntu.

I VERY much doubt you will get any satisfaction from playing around in the Ubuntu settings, even if you could see them!

It seems to be a refresh rate or horizontal frequency mode problem, the screen will just blank if the tv is unable to display them.

[glubbish]

More info:

nuc:
NUC6i7KYK
BIOS Version: 0066 (Latest) Date: 12/5/2019

There was no option for intel idg in the bios

I tried using the menus on the LG, what a difficult mess that is.
This tv seems to insist that you choose between certain devices, none of which work
I could not find any way to change any setting for the device.
The manual is next to useless

[vidtek]

More info:

nuc:
NUC6i7KYK
BIOS Version: 0066 (Latest) Date: 12/5/2019

There was no option for intel idg in the bios

I tried using the menus on the LG, what a difficult mess that is.
This tv seems to insist that you choose between certain devices, none of which work
I could not find any way to change any setting for the device.
The manual is next to useless

My next suggestion would be to return the tv from where you purchased it. If it is that difficult to operate it is not fit for purpose.

If that is not an option, try this forum:

https://www.avforums.com/forums/

Post your questions there, maybe someone else has that model and can give you some guidance.

Sounds like it is quite a dud.

Cheers Tony.

[glubbish]

Managed to get it to display after:
export DISPLAY=:0
xrandr --output DP-1 --mode 1920x1080 --rate 60

so its working for 1080

Prior to this xrandr showed:

chris@kodi:~$ export DISPLAY=:0
chris@kodi:~$ xrandr
Screen 0: minimum 320 x 200, current 3840 x 2160, maximum 8192 x 8192
DP-1 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 1600mm x 900mm
3840x2160 30.00*+ 25.00 24.00 29.97 23.98
4096x2160 30.00 25.00 24.00 29.97 23.98
1920x1080 120.00 100.00 119.88 60.00 50.00 59.94 30.00 25.00 24.00 29.97 23.98
1920x1080i 60.00 50.00 59.94
2880x576 50.00
2880x480 60.00 59.94
1280x1024 60.02
1152x864 59.97
1280x720 60.00 50.00 59.94
1440x576 50.00
1024x768 60.00
1440x480 60.00 59.94
800x600 60.32
720x576 50.00
720x480 60.00 59.94
640x480 60.00 59.94
720x400 70.08
DP-2 disconnected (normal left inverted right x axis y axis)
HDMI-1 disconnected (normal left inverted right x axis y axis)
DP-3 disconnected (normal left inverted right x axis y axis)
HDMI-2 disconnected (normal left inverted right x axis y axis)
chris@kodi:~$

[vidtek]

Managed to get it to display after:
export DISPLAY=:0
xrandr --output DP-1 --mode 1920x1080 --rate 60

so its working for 1080

Prior to this xrandr showed:

chris@kodi:~$ export DISPLAY=:0
chris@kodi:~$ xrandr
Screen 0: minimum 320 x 200, current 3840 x 2160, maximum 8192 x 8192
DP-1 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 1600mm x 900mm
3840x2160 30.00*+ 25.00 24.00 29.97 23.98
4096x2160 30.00 25.00 24.00 29.97 23.98
1920x1080 120.00 100.00 119.88 60.00 50.00 59.94 30.00 25.00 24.00 29.97 23.98
1920x1080i 60.00 50.00 59.94
2880x576 50.00
2880x480 60.00 59.94
1280x1024 60.02
1152x864 59.97
1280x720 60.00 50.00 59.94
1440x576 50.00
1024x768 60.00
1440x480 60.00 59.94
800x600 60.32
720x576 50.00
720x480 60.00 59.94
640x480 60.00 59.94
720x400 70.08
DP-2 disconnected (normal left inverted right x axis y axis)
HDMI-1 disconnected (normal left inverted right x axis y axis)
DP-3 disconnected (normal left inverted right x axis y axis)
HDMI-2 disconnected (normal left inverted right x axis y axis)
chris@kodi:~$

If this is now solved please mark it so; glad you got it going, where did you get the idea for the solution?
Tony

[glubbish]

not quite solved.
It still does not work with 4k.
Got the idea from the kodi forum
https://forum.kodi.tv/showthread.php?tid=352003

[vidtek]

not quite solved.
It still does not work with 4k.
Got the idea from the kodi forum
https://forum.kodi.tv/showthread.php?tid=352003

It is really helpful for others who may encounter these issues if you write out the steps you have taken to (partially) resolve the situation.
When they do an internet search this thread will appear in it.
It is all about helping each other.
Cheers Tony.

[glubbish]

Still not having a lot of luck with this issue.

Found that running:
xrandr --output DP-1 --mode 1920x1080 --rate 60
from a remote terminal does make the session visible on the tv

But this also changes the sound (pulseaudio) from hdmi to analog and does not work.

I created a script called set_screen_resolution.sh

#!/bin/bash
xrandr --output DP-1 --mode 1920x1080  --rate 60
pactl set-card-profile 0  output:hdmi-surround

and running this after boot fixes both the display and the sound

I tried to automate this script using crontab -e including

@reboot sleep 90 && /home/chris/set_screen_resolution.sh

But it does not do anything and xrandr shows the wrong resolution
but if I do

$./set_screen_resolution.sh

it works fine.

[glubbish]

Finally got a workaround for this by creating a file in ~/.config/autostart
containing
xrandr --output DP-1 --mode 1920x1080 --rate 60
pactl set-card-profile 0 output:hdmi-surround