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xorg package

Monitor detection apparently fails after using a data projector

Asked by Jonathan Keeling

I normally connect my laptop to an external monitor, which is detected correctly, and xrandr offers the full range of resolutions that the monitor can support. If I connect my laptop to a data projector, and then reconnect to my external monitor, the capabilities of the monitor no longer seem to be detected, and a limited set of resolutions is available. It may be that this is also true of the data projector, i.e. that any attempt to connect to more than one external monitor without rebooting in between causes this problem, however typically the data projectors I connect to only support 1024x768, so it is harder to spot this.

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actionparsnip (andrew-woodhead666) said : 		#1

I recommend you restart the X server inbetween connecting the devices.

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Jonathan Keeling (jmjk2) said : 		#2

Unfortunately this does not work. (Neither logging out and logging in, nor by restarting gdm). In both cases, I do not have the same set of resolutions available for the external monitor as I do after rebooting.

I can add the required resolution manually by using:

xrandr --newmode "big" 146.25 1680 1784 1960 2240 1050 1053 1059 1089 -hsync +vsync
xrandr --addmode VGA1 big

but presumably this ought not to be necessary.

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actionparsnip (andrew-woodhead666) said : 		#3

You could log a bug and make a script of the commands you run. You can then use it more easily.

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