Have X always display only on VGA output?

Felix Miata mrmazda at earthlink.net
Fri Nov 29 00:23:28 PST 2013

On 2013-11-28 21:37 (GMT-0800) Sandeep composed:
What gfxchip do you have (output from 'lspci | grep VGA')?
Is there any video on the external display during boot? If so, exactly when 
does it stop?

If what Matthias and Fernando suggested work, fine. If not, remember that X 
can still be controlled via /etc/X11/xorg.conf*. KDE throws a fly in that 
ointment in the form of Kscreen, so to make my suggestions work you'll need 
to put


in /etc/kde(4)/share/config/kdedrc if it exists, or create one if it doesn't, 
for use at least until you get the no external output problem eradicated.

Next you'll need either




Which to choose is a matter of personal preference, but the combined content 
of the three separates will be no different than that of the single. 
Following may be all you need (subject to conforming the monitor-XXX string's 
tail to match what you find in Xorg.0.log for your laptop's VGA output):

# 50-device.conf
Section "Device"
	Identifier "Default Device"
	Option "monitor-VGA1" "Default Monitor"

# 50-monitor.conf
Section "Monitor"
	Identifier "Default Monitor"

# 50-screen.conf
Section "Screen"
	Identifier "Default Screen"
	Device "Default Device"
	Monitor "Default Monitor"

If it doesn't work, device section might need also:

	Option "monitor-LVDS" "Off"

or adding to the device section:

	   Option "monitor-LVDS" "LVDS"

Plus an additional monitor section:

Section "Monitor"
	Identifier "LVDS"
	Option "Ignore" "true"

See e.g.: http://www.thinkwiki.org/wiki/Xorg_RandR_1.2 &
"The wise are known for their understanding, and pleasant
words are persuasive." Proverbs 16:21 (New Living Translation)

  Team OS/2 ** Reg. Linux User #211409 ** a11y rocks!

Felix Miata  ***  http://fm.no-ip.com/

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