[CentOS] dual head on laptop

Sudev Barar sbarar at gmail.com
Thu Nov 24 02:19:49 UTC 2005

On 11/24/05, Rodrigo Barbosa <rodrigob at suespammers.org> wrote:
> On Wed, Nov 23, 2005 at 09:01:42AM +0100, Peter van Eck wrote:
> > My experience is that when I plug in the projector  while X is already
> > running it loses sync..basically a black screen...
> >
> > But when I start X while connected to the projector it displays fine
> > (1024x768)..
> > This is a HP pavilion ze4900 (with i810 video card)...
> it can get worst than that. In a few cases (mostly Compaq), if you
> don't have the projector connected before you turn the notebook
> on, you don't even get the text boot sequence to show. Using the
> function keys on the keyboard you get the feeling that the SVGA
> port is being activated (the LCD screen blanks etc etc), but you
> still get no image.

Way out:
1. Connect the projector
2. Switch to console with Alt+Ctl+F1 (or F2...)
3. Toggle to projector setting (or shared setting) As you are in text
the projector will beam the command line.
4. Start another X session by command startx -- :1

This works for me almost always subject to X resolution being within
power of projector. By experience mostly 1024x768 works.

Sudev Barar
Learning Linux

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