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Doughy
September 18th, 2008, 06:35 AM
Does anyone know why I have to restart X (CTRL+ALT+BKSP) to get a projector to work with Ubuntu? I have to plug in the projector, then restart X, then re-login, then restart my presentation. I was giving a talk at a professional conference and it was embarrassing that my linux machine didn't work right away when I plugged in the projector. One judge even came up to me and said "Don't give presentations on Linux" when I was done. Great....

Anyone know if this issue will be fixed? Links to bugs or future plans? Thanks.

chewearn
September 18th, 2008, 07:30 AM
First obvious question is: what graphics card do you have (Intel, ATI, NVIDIA)?

If in doubt, run this command, post the output here:

lspci | grep VGA

Doughy
September 18th, 2008, 07:34 AM
First obvious question is: what graphics card do you have (Intel, ATI, NVIDIA)?

If in doubt, run this command, post the output here:

lspci | grep VGA

00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 0c)

chewearn
September 18th, 2008, 07:49 AM
Ah, it should be relatively easy to hack around the problem for this Intel graphics. Note: there are bugs filed for fixing all these, but it seemed to be slow going in the launchpad.

I found this webpage to be helpful in fixing Intel graphics: http://www.thinkwiki.org/wiki/Xorg_RandR_1.2

Unfortunately, the Ubuntu screen resolution utility doesn't work so well, so it is better to use command line xrandr.

First you define a large virtual screen. I recommend the current "working" max, which is 2048x2048. You have to edit xorg.conf and add these lines under: Section "Screen":


SubSection "Display"
Vrtual 2048 2048
EndSubSectionYou only need to do this once. Restart Xorg after changing the file.

Now, you can set dual screen dynamically. Some example commands:

Find out detected displays:

xrandr -qSet dual screens; external screen to the right of internal screen:

xrandr --output LVDS --auto --output VGA --auto --right-of LVDSSet back to single screen:

xrandr --output LVDS --auto --output VGA --offIt just happened I was mucking around with the same thing yesterday, and was planning to write a comprehensive blog post about this fix. Look out for it, if you are interested.