Cfxtrjtrk

I want to use a second screen. To do so I would like to plug in an HDMI cable to connenct an external monitor. I already tried to connect two different monitors and they seem to recognise something on booting, but they shutdown shortly after, saying "No Signal".

I am using a Dell G3 15:

- Linux 5.0.6

- Ubuntu 18.04 (x86-64)

- Cinnamon 3.6.7

- Intel Core i7-8750H

- 8GB Ram

- Nvidia GTX 1050 Ti mobile

I thought of a graphics driver problem. That is why I added

ppa:graphics-drivers 

and tried out several nvidia drivers. Versions 390 and 396 seem to work, but 410, 415 and 418 will lead to a failure while booting.

I can show you my status at the moment via

~$ ubuntu-drivers devices



== /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0 ==

modalias : pci:v000010DEd00001C8Csv00001028sd0000086Fbc03sc02i00

vendor   : NVIDIA Corporation

model    : GP107M [GeForce GTX 1050 Ti Mobile]

driver   : nvidia-driver-415 - third-party free

driver   : nvidia-driver-390 - distro non-free

driver   : nvidia-driver-418 - third-party free recommended

driver   : nvidia-driver-396 - third-party free

driver   : nvidia-driver-410 - third-party free

driver   : xserver-xorg-video-nouveau - distro free builtin

To list my devices:

~$ lspci | grep VGA



00:02.0 VGA compatible controller: Intel Corporation Device 3e9b

~$ lspci | grep NVIDIA



01:00.0 3D controller: NVIDIA Corporation GP107M [GeForce GTX 1050 Ti Mobile] (rev a1)

01:00.1 Audio device: NVIDIA Corporation GP107GL High Definition Audio Controller (rev a1)

I also get an error message using xrandr: "Failed to get size of gamma for output default"

~$ xrandr

xrandr: Failed to get size of gamma for output default

Screen 0: minimum 1920 x 1080, current 1920 x 1080, maximum 1920 x 1080

default connected primary 1920x1080+0+0 0mm x 0mm

   1920x1080     77.00* 

I hope someone has a clue what is going on.

I appreciate your invested time. Thank you.

Edit:
So I ran cat /proc/cmdline and it gave me nomodeset (end of the line).

By changing /etc/default/grub as well as removing an additional directory called /etc/default/grub.d/ I could boot and call xrandr again giving me the following:

xrandr

Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192

eDP-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 194mm

   1920x1080     60.02 +  60.01*   59.97    59.96    59.93    48.03  

   1680x1050     59.95    59.88  

   1600x1024     60.17  

   1400x1050     59.98  

   1600x900      59.99    59.94    59.95    59.82  

   1280x1024     60.02  

   1440x900      59.89  

   1400x900      59.96    59.88  

   1280x960      60.00  

   1440x810      60.00    59.97  

   1368x768      59.88    59.85  

   1360x768      59.80    59.96  

   1280x800      59.99    59.97    59.81    59.91  

   1152x864      60.00  

   1280x720      60.00    59.99    59.86    59.74  

   1024x768      60.04    60.00  

   960x720       60.00  

   928x696       60.05  

   896x672       60.01  

   1024x576      59.95    59.96    59.90    59.82  

   960x600       59.93    60.00  

   960x540       59.96    59.99    59.63    59.82  

   800x600       60.00    60.32    56.25  

   840x525       60.01    59.88  

   864x486       59.92    59.57  

   800x512       60.17  

   700x525       59.98  

   800x450       59.95    59.82  

   640x512       60.02  

   720x450       59.89  

   700x450       59.96    59.88  

   640x480       60.00    59.94  

   720x405       59.51    58.99  

   684x384       59.88    59.85  

   680x384       59.80    59.96  

   640x400       59.88    59.98  

   576x432       60.06  

   640x360       59.86    59.83    59.84    59.32  

   512x384       60.00  

   512x288       60.00    59.92  

   480x270       59.63    59.82  

   400x300       60.32    56.34  

   432x243       59.92    59.57  

   320x240       60.05  

   360x202       59.51    59.13  

   320x180       59.84    59.32  

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

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

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

Although I would see that as a step foreward, I don't know why there is shown a DP-1 and a HDMI-1-2 port, because I only got one HDMI port and still I can't send a signal to an external monitor.

So I kind of fixed my problem.

While being logged in I restarted the lightdm service. As I did so, my second screen (hdmi connected) turned on, but my primary screen turned off. In xrandr and arandr only hdmi1 was active. Afterwards I stopped the lightdm service and rebooted my system. I can use both of my screens now.

Unfortunately I am not sure if this solution can be reproduced. But the source of my error got identified. My xrandr shows HDMI-0 connected.

~$ xrandr

Screen 0: minimum 8 x 8, current 3840 x 1080, maximum 32767 x 32767

HDMI-0 connected 1920x1080+1920+0 (normal left inverted right x axis y axis) 510mm x 290mm

   1920x1080     60.00*+  59.94    50.00    60.05    60.00    50.04  

   1680x1050     59.95  

   1600x900      60.00  

   1440x900      59.89  

   1400x1050     59.98  

   1280x1024     60.02  

   1280x800      59.81  

   1280x720      60.00    59.94    50.00  

   1152x864      60.00  

   1024x768      60.00  

   800x600       60.32  

   720x576       50.00  

   720x480       59.94  

   640x480       59.94    59.93  

eDP-1-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 194mm

   1920x1080     60.02*+  60.01    59.97    59.96    59.93    48.03  

   1680x1050     59.95    59.88  

   1600x1024     60.17  

   1400x1050     59.98  

   1600x900      59.99    59.94    59.95    59.82  

   1280x1024     60.02  

   1440x900      59.89  

   1400x900      59.96    59.88  

   1280x960      60.00  

   1440x810      60.00    59.97  

   1368x768      59.88    59.85  

   1360x768      59.80    59.96  

   1280x800      59.99    59.97    59.81    59.91  

   1152x864      60.00  

   1280x720      60.00    59.99    59.86    59.74  

   1024x768      60.04    60.00  

   960x720       60.00  

   928x696       60.05  

   896x672       60.01  

   1024x576      59.95    59.96    59.90    59.82  

   960x600       59.93    60.00  

   960x540       59.96    59.99    59.63    59.82  

   800x600       60.00    60.32    56.25  

   840x525       60.01    59.88  

   864x486       59.92    59.57  

   800x512       60.17  

   700x525       59.98  

   800x450       59.95    59.82  

   640x512       60.02  

   720x450       59.89  

   700x450       59.96    59.88  

   640x480       60.00    59.94  

   720x405       59.51    58.99  

   684x384       59.88    59.85  

   680x384       59.80    59.96  

   640x400       59.88    59.98  

   576x432       60.06  

   640x360       59.86    59.83    59.84    59.32  

   512x384       60.00  

   512x288       60.00    59.92  

   480x270       59.63    59.82  

   400x300       60.32    56.34  

   432x243       59.92    59.57  

   320x240       60.05  

   360x202       59.51    59.13  

   320x180       59.84    59.32  

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

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

  1680x1050 (0x4c) 146.250MHz -HSync +VSync

        h: width  1680 start 1784 end 1960 total 2240 skew    0 clock  65.29KHz

        v: height 1050 start 1053 end 1059 total 1089           clock  59.95Hz

  1280x1024 (0x54) 108.000MHz +HSync +VSync

        h: width  1280 start 1328 end 1440 total 1688 skew    0 clock  63.98KHz

        v: height 1024 start 1025 end 1028 total 1066           clock  60.02Hz

  1440x900 (0x55) 106.500MHz -HSync +VSync

        h: width  1440 start 1520 end 1672 total 1904 skew    0 clock  55.93KHz

        v: height  900 start  903 end  909 total  934           clock  59.89Hz

  1280x800 (0x61) 83.500MHz -HSync +VSync

        h: width  1280 start 1352 end 1480 total 1680 skew    0 clock  49.70KHz

        v: height  800 start  803 end  809 total  831           clock  59.81Hz

  1152x864 (0x63) 81.620MHz -HSync +VSync

        h: width  1152 start 1216 end 1336 total 1520 skew    0 clock  53.70KHz

        v: height  864 start  865 end  868 total  895           clock  60.00Hz

  1024x768 (0x69) 65.000MHz -HSync -VSync

        h: width  1024 start 1048 end 1184 total 1344 skew    0 clock  48.36KHz

        v: height  768 start  771 end  777 total  806           clock  60.00Hz

  800x600 (0x78) 40.000MHz +HSync +VSync

        h: width   800 start  840 end  968 total 1056 skew    0 clock  37.88KHz

        v: height  600 start  601 end  605 total  628           clock  60.32Hz

  640x480 (0x87) 25.175MHz -HSync -VSync

        h: width   640 start  656 end  752 total  800 skew    0 clock  31.47KHz

        v: height  480 start  490 end  492 total  525           clock  59.94Hz

Anyway, I am glad it now works as intended.

Edit:
So I may have found a solution.

In my foulder /etc/X11/ there are two relevant files:

/etc/X11/defualt-display-manager

/etc/X11/defualt-display-manager.dpkg-tmp

Within the first one there is my default display manager defined: lightdm. I am not quite sure what the second file defines, but there is another display manager listed: gdm3. Both files just contain one single line. I just uncommented the gdm3 line in the second file and now my setup runs properly.

Hope it helps.