5

After my update from 12.04 to 13.10 my display configuration started showing an extra unknown monitor, even though I have nothing connected.

enter image description here

lscpi:

00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)
01:00.0 VGA compatible controller: NVIDIA Corporation GF108M [GeForce GT 540M] (rev a1)

xrandr

Screen 0: minimum 320 x 200, current 1366 x 768, maximum 32767 x 32767
LVDS1 connected primary 1366x768+0+0 (normal left inverted right x axis y axis) 344mm x 194mm
   1366x768       60.0*+   60.1  
   1360x768       59.8     60.0  
   1024x768       60.0  
   800x600        60.3     56.2  
   640x480        59.9  
VGA1 disconnected (normal left inverted right x axis y axis)
HDMI1 disconnected (normal left inverted right x axis y axis)
DP1 disconnected (normal left inverted right x axis y axis)
VIRTUAL1 disconnected (normal left inverted right x axis y axis)
VGA-2 connected (normal left inverted right x axis y axis)
   1024x768       60.0  
   800x600        60.3     56.2  
   848x480        60.0  
   640x480        59.9  
  1024x768 (0x43)   65.0MHz
        h: width  1024 start 1048 end 1184 total 1344 skew    0 clock   48.4KHz
        v: height  768 start  771 end  777 total  806           clock   60.0Hz
  800x600 (0x44)   40.0MHz
        h: width   800 start  840 end  968 total 1056 skew    0 clock   37.9KHz
        v: height  600 start  601 end  605 total  628           clock   60.3Hz
  800x600 (0x45)   36.0MHz
        h: width   800 start  824 end  896 total 1024 skew    0 clock   35.2KHz
        v: height  600 start  601 end  603 total  625           clock   56.2Hz

This problem seems to had been previously asked here and here.

Any ideas on how to solve this?

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Presbitero
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2 Answers2

5

I have finally found a working solution in these two questions: one, two

Basically one needs to edit sudo gedit /etc/default/grub and replace

GRUB_CMDLINE_LINUX=""

by

GRUB_CMDLINE_LINUX="video=VGA-2:d"

where VGA-2 is the name of the incorrectly connected display shown by xrandr.

Run 

sudo update-grub

and reboot

Community
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Presbitero
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  • Same NVIDIA issue. :( For me, it's named VGA-1-2.

    Above solution didn't work out of the box due to uncertain reason, so here is what additional things I performed to disable that 'Unknown Display' in Ubuntu GNOME 14.04.

    Removed entries respected toVGA-1-2 from config file ~/.config/monitors.xml and executed below command to disable all VGA as I don't use any VGA. echo xrandr --output vga --off >> ~/.xinitrc and finally sudo reboot :)

     – Mayura May 06 '14 at 02:30
0

Yeah this happened with me on my fresh ubuntu 13.10 install, no idea why, I disable it and it works fine. it pops back up when connecting a secondary monitor to my laptop but just disable it again. I think its a display driver issue

IceTimux
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