secondary screen only works until login

[Dave Stevens]

On Tue, 29 Aug 2017 21:53:11 +0200
Xen <list at xenhideout.nl> wrote:

> Dave Stevens schreef op 29-08-2017 20:57:
> > Hi,
> > 
> > I'm using 16.04 on a Toshiba laptop. I want to use a secondary
> > display, a Samsung SyncMaster 712n. I have it connected to the
> > Toshiba's external VGA port. The display powered up and showed
> > system activity right up until the automatic user login took place.
> > I had the system configured to log me in without asking for a
> > password. When the login took place the secondary display went
> > blank. The system control panel shows an unknown secondary display.
> > 
> > In an attempt to see where the problem lies I made a new (second)
> > user with a password and required a credential check at login. When
> > I log in as the new user the secondary screen mirrors the main
> > laptop screen and continues to work until I logout then log back in
> > as the previous (admin) user, then it blanks.
> > 
> > I suppose if I knew more about the graphic setup this would tell me
> > where to look for more info but I don't.
> > 
> > Anyone have a suggestion about where to look?  
> 
> Yes always just look at xrandr I guess.
> 
> xrandr is a tool you can use to make those changes.
> 
> Of course rather tiring to have to use it by hand.
> 
> xrandr -q will list all connected (and unconnected) displays in your 
> system.
> 
> xrandr --output DVI-I-1 --primary --output HDMI-I-1 --clone
> 
> for example should, if DVI-I-1 exists, make that the primary display, 
> and I think this would copy that screen to the HDMI-I-1 if it exists.
> 
> So the syntax is basically first --output NAME and then --something
> to affect it.
> 
> You can also set resolution with --display 1440x900 or something and 
> --scale 1.4x1.0 or something, or --scale-from 1440x900 or something.
> 
> --auto will do auto configuration.
> 
> If you figure out how to do it you can create a desktop shortcut to
> do it etc.
> 
> Good luck.
> 

ooh! ooh! you da man! got it, and easy too. Thanks!

d


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