Can't connect a second monitor through HDMI

MeinzBeur · 01-10-2021, 02:03 PM

Hei everyone,
I know such issues have already been posted in many places before, but no forum thread could solve my issue.

The title says most of it: I can't connect a monitor to my laptop using the HDMI port.

My laptop: ACER aspire V nitro. Intel Core i7 and a GeForce GTX 960M graphic card (the NVIDIA card is being used all the time, not the Intel integrated graphics). I do not have any other video port than the HDMI.
I run pop os 20.10, but I had the same issue before when I had ubuntu (since 5 years more or less).

If I run xrandr with the monitor connected, I get this output:

Code:

DP-1-1 disconnected (normal left inverted right x axis y axis)
HDMI-1-1 disconnected (normal left inverted right x axis y axis)
DP-1-2 disconnected (normal left inverted right x axis y axis)
HDMI-1-2 disconnected (normal left inverted right x axis y axis)

I did not include the part about my eDP-1-1 primary screen. First question here: Why are there 2 HDMI output?

I have used many times the add mode in xrandr:

Code:

]xrandr --addmode HDMI-1-1 "1920x1080"
xrandr --output HDMI-1-1 --mode  1920x1080

That did the job many times for external monitors and beamers, but:
* It is not permanent (I know), but it also disconnect the screen when the computer goes to sleep after 10 mins. Pretty annoying.
* If I change the code to place the monitor "to the right" rather than a duplicate of the main screen it does not work. Well, it appears, but it is not usable due to many glitches.
* I just bought an Acer Predator XB241 monitor. With this monitor xrandr does not work at all... no idea why.

So I did look a bit around for solutions. There are 2 solutions here that seemed interesting:
https://www.dell.com/community/Preci.../7286631#M1634
https://forums.developer.nvidia.com/...-display/79577
However I can't get to try them cause I do not have the files they speak about. One reason may be that with pop os I actually do not have NVIDIA prime, but a pop os power control alternative as default. So I tried to install NVIDIA prime (removing the pop os power control utility), which led to my computer not being able to boot at all... I had to go in the grub and fix my pop os installation.

So right now I do not know what to do... I would like to get my laptop to recognise automatically the external monitors, without using xrandr each time.
Thanks for the help.

business_kid · 01-11-2021, 07:23 AM

You can write a config file and put it in /etc/X11.xorg.conf.d/10-video.conf

Pattern it after the Video Section of 'man xorg.conf.' It has to have a ServerLayout, Monitor, Device, & Screen subsections. On startup, X will feel around for what is attached and use what is connected.

MeinzBeur · 01-11-2021, 08:02 AM

Hei.
thanks for the answer. I however do not understand much...
First there is no Video section in 'man xorg.conf'. There is however a 'videoadaptor' section, which says: Nobody wants to say how this works. Maybe nobody knows...
Second, even if I would see what the layout should be, I would not have any idea what to put in. I understand really little of how all that works.

business_kid · 01-11-2021, 03:12 PM

Yeah, it has changed. Ignore the videoadapter. The rest is there.

ServerLayout
Device
Monitor
Screen

In my defense, the last time I had to use one was April 2015, and I had health issues since. They have changed it around a bit. The video adapter, iirc dates to the early days in the 1990s where you had one totally sucky video card or the other, there was a plethora of card manufacturers, and everyone was experimenting on the unsuspecting public. You also had dodgy systems with drivers so bad that they ran faster on vesa or frame buffer. So your video adapter was a chip, but your driver could be frame buffer, vesa, or even some other chip. And there were two versions of some chips, e.g. S3, & S3 Virge, with incompatible drivers:-/.

kilgoretrout · 01-11-2021, 03:25 PM

You're running PopOS which is a Ubuntu based distro with a modified Gnome DE. Don't know the current state of Gnome but in the past there were problems in Gnome with multi-monitor support. You may want to try a livecd of a KDE based distro like Kubuntu or KDE Neon and see if the multi-monitor support is better there with your hardware.

MeinzBeur · 01-12-2021, 12:29 PM

@business_kid. Hum, ok, but that does not change anything to the fact that I do not understand anything about what you advise me to do. I tried to read the man output, but I still do not get anything. Sorry...

@kilgoretrout. Ok, did not know that. I am however not willing to move away from pop os, so I would use your solution as last resort. I can't imagine that there is not way to fix the issue though. I have several friends running on ubuntu and having no issue with external monitors.

business_kid · 01-12-2021, 01:24 PM

OK. This link https://mega.nz/file/iY1njIZb#RveSxg...OiEBj8rGYWt-Ws is to my 20-video.conf from way back. I was setting up for

My Primary Monitor on the Laptop 1600×900 screen
Some projector with a 1280×720 output on hdmi.
A Normal HDMI Monitor on the hdmi output.
Anything hanging out of the vga cable, if anything was there.

Some caveats with this file are

All the duplication in the Device section are unnecessary.
X needs no modelines.
Some of the options are gone from the code. I may have some of the dead ones commented out.

The way this worked was that left screen was the laptop, and right screen was the projector. Everything came up in the left, and what I wanted to project had to be dragged over to the right. It did the job. Position is Position in the Virtual Screen. My laptop is 1600x900, so 1601,0 is the top left corner of the right screen. Use that as starting material and knock yourself out.

MeinzBeur · 01-12-2021, 01:59 PM

Thanks! I ll give a shot and let you know how it works!

mrmazda · 01-12-2021, 10:56 PM

Using this /etc/X11/xorg.conf:

Code:

# 50-device.conf
Section "Device"
        Identifier      "Only"
        Option  "monitor-DP-2"  "upperCon2"
        Option  "monitor-DP-1"  "lowerCon1"
EndSection

# 50-monitor1.conf
Section "Monitor"
        Identifier      "lowerCon1"
        Option          "Primary"       "true"
        Option          "DPMS"  "off"
EndSection

# 50-monitor2.conf
Section "Monitor"
        Identifier      "upperCon2"
        Option          "Above" "lowerCon1"
        Option          "DPMS"  "off"
EndSection

# 50-screen1.conf
Section "Screen"
        Identifier      "ScreenUnder"
        Device          "Only"
        Monitor         "lowerCon1"
EndSection

# 50-screen2.conf
Section "Screen"
        Identifier      "ScreenOver"
        Device          "Only"
        Monitor         "upperCon2"
EndSection

I was able to produce this over/under two display result:

Code:

# inxi -IS
System:    Host: p5bse Kernel: 5.3.18-lp152.41-default x86_64 bits: 64 Desktop: KDE 3 Distro: openSUSE Leap 15.2
Info:      Processes: 161 Uptime: 1h 11m Memory: 3.84 GiB used: 633.5 MiB (16.1%) Shell: Bash inxi: 3.2.02

# inxi -Gay
Graphics:
  Device-1: NVIDIA GF119 [NVS 310] vendor: Hewlett-Packard driver: nouveau
  v: kernel bus ID: 01:00.0 chip ID: 10de:107d
  Display: server: X.Org 1.20.3 driver: loaded: modesetting
  unloaded: fbdev,vesa alternate: nouveau,nv,nvidia display ID: :0 screens: 1
  Screen-1: 0 s-res: 2560x2520 s-dpi: 120 s-size: 541x533mm (21.3x21.0")
  s-diag: 759mm (29.9")
  Monitor-1: DP-1 res: 2560x1440 hz: 60 dpi: 109 size: 598x336mm (23.5x13.2")
  diag: 686mm (27")
  Monitor-2: DP-2 res: 2560x1080 hz: 60 dpi: 97 size: 673x284mm (26.5x11.2")
  diag: 730mm (28.8")
  OpenGL: renderer: llvmpipe (LLVM 9.0.1 128 bits) v: 3.3 Mesa 19.3.4
  compat-v: 3.1 direct render: Yes

# xrandr | egrep 'onnect|creen|\*' | grep -v disconn | sort -r
Screen 0: minimum 320 x 200, current 2560 x 2520, maximum 16384 x 16384
DP-2 connected 2560x1080+0+0 (normal left inverted right x axis y axis) 673mm x 284mm
DP-1 connected primary 2560x1440+0+1080 (normal left inverted right x axis y axis) 598mm x 336mm
   2560x1440     59.95*+  74.92
   2560x1080     60.00*+

It's not a laptop, nor does it have dual graphics, nor HDMI ports, but it should be functional as a template for building an xorg.conf that positions the displays as you wish, if over/under is your wish. Side-by-side is the default.

Note the absence of:

a ServerLayout section in xorg.conf
absence of a driver specification in the Device section in xorg.conf
absence of NVidia, Intel and Nouveau DDX drivers in inxi output

This xorg.conf could be split up into files named as indicated by its comments and placed in /etc/X11/xorg.conf.d/, which might make developing a configuration that works for your laptop easier.