Issues using external monitor with Laptop

[rinjo]

Hi All,

I am using a HP laptop with a dual boot configuration.
I recently got an external monitor, since I my laptop display has developed some issues.

In my Windows XP installation, I can switch between the laptops display and the external monitor using the Fn+F4 key, and there are no issues with it.

I run into resolution issues when I switch onto my Linux installation. I am running F10 with 2.6.27.41-170.2.117.fc10.i686 kernel and Gnome 2.24.3.
F10 is able to detect the external monitor.
I am still having my laptop display as the primary display, and I do not get anything on the external monitor during F10 boot. I directly get the login screen.

Issues that I am facing:

1. F10 is using a default resolution of 1024x768 for the external display, but the actual resolution for the display is 1360x768.
In F10 xorg.conf is not used. I googled for this issue and yum installed xorg.conf and then modified the same, but to no use. The display still shows the lower resolution.

I am attaching copy of my xorg.conf. Please help me sort this issue.

# Xorg configuration created by system-config-display

Section "ServerLayout"
        Identifier     "single head configuration"
        Screen      0  "Screen0" 0 0
        InputDevice    "Keyboard0" "CoreKeyboard"
EndSection

Section "InputDevice"

# keyboard added by rhpxl
        Identifier  "Keyboard0"
        Driver      "kbd"
        Option      "XkbModel" "pc105+inet"
        Option      "XkbLayout" "us"
EndSection

Section "Monitor"
        Identifier   "Monitor0"
        ModelName    "LCD Panel 1360x768"
        HorizSync    31.5 - 48.0
        VertRefresh  56.0 - 65.0
        Option      "dpms"
EndSection

Section "Device"
        Identifier  "Videocard0"
        Driver      "intel"
EndSection

Section "Screen"
        Identifier "Screen0"
        Device     "Videocard0"
        Monitor    "Monitor0"
        DefaultDepth     24
        SubSection "Display"
                Viewport   0 0
                Depth     24
                Modes    "1360x768"
        EndSubSection
EndSection

2. I want to use the external monitor as the only display. Present, both the external display and my laptop display are ON at the same time.

3. One more thing that I noticed today is that I cannot change to the terminals using ctrl+alt+f2...f7.
The display disappears from the external monitor and is only available on the laptop display.

Plz help!!!

Thanks in advance.

--Rinjo

[David Batson]

Maybe the information in these posts will help to get your problem resolved.

Use xmodmap to remap keys if needed.
http://forums.fedoraforum.org/showpo...6&postcount=19

Create a shortcut.
https://bugzilla.gnome.org/show_bug.cgi?id=603891#c13

Create a script to run with your hotkey combo (see bottom portion of following post).
http://forums.fedoraforum.org/showpo...61&postcount=4

[rinjo]

Hi David,

Appreciate the prompt response.
I will check out the posts that you have mentioned in the evening today and get back.

Cheers
-Rinjo

[David Batson]

There is some information about using xrandr in this bug report you may find useful as well (even though it's a KDE bug report).
https://bugs.kde.org/show_bug.cgi?id=180437

[rinjo]

Hi David,

Thanks a lot for the reference posts you had mentioned in your link.
xrandr helped in setting the display correct.

I have used the following code to set the display of my external monitor correct.

[rinjo@localhost ~]$ xrandr --output VGA --mode 1366x768

This sorted out the display resolution issue.

I have one more query...
In all the posts that you had referred spoke of using both the laptop and external monitor displays.
Is there some method by which I can use only the external display as the primary display?

Cheers
-Rinjo

[David Batson]

#!/bin/sh

statusvga=`xrandr -q | grep 1024x768* | grep VGA-0 | cut -c1-5`
statuslvds=`xrandr -q | grep "1400x1050*\|1024x768*" | grep LVDS | cut -c1-4`

if [ "$statusvga" != "VGA-0" ] && [ "$statuslvds" == "LVDS" ] ; then
   xrandr --output LVDS --mode 1400x1050 --output VGA-0 --auto --right-of LVDS
fi
if [ "$statusvga" == "VGA-0" ] && [ "$statuslvds" == "LVDS" ] ; then
   xrandr --output LVDS --off
fi
if [ "$statusvga" == "VGA-0" ] && [ "$statuslvds" != "LVDS" ] ; then
   xrandr --output LVDS --mode 1400x1050 --output VGA-0 --off
fi
exit

In the script I created above which toggles the displays...

If test 1 is true (external display off and laptop display on), then the script issues the command: xrandr --output LVDS --mode 1400x1050 --output VGA-0 --auto --right-of LVDS to turn the external display on and position it to the right of the laptop display. EDITED

If test 2 is true (external display on and laptop display on), then the script issues the command: xrandr --output LVDS --off to turn the laptop display off (leaving the external display on).

If test 3 is true (external display on and laptop display off), then the script issues the command: xrandr --output LVDS --mode 1400x1050 --output VGA-0 --off to turn the laptop display on and turn the external display off.

It would seem that you want to issue the command I have if test 2 is true because both dislays are on but you want to shut off the laptop display, leaving the external display on. I can't say that my script would exactly fit your situation since my display identifications and resolutions might be different from yours. You could issue the command xrandr -q to get this information.

[rinjo]

Hi David,

Thanks for the shell script. I can change the values in the script according to my needs.
The $ xrandr --output LVDS --off when run as is will be switching off the laptop display.
I checked the xrandr man page but did not find any --on option.

Just curious, if I run the following command is the only way of turn on the laptop display?
$ xrandr --output LVDS --mode 1280x800

Cheers
-Rinjo

[David Batson]

I am not a xrandr expert. I just pick up things here and there when I need them. There is an 'auto' switch for xrandr.

http://www.thinkwiki.org/wiki/Xorg_R..._useful_things

[rinjo]

Thanks David for the link to Xrandr useful things.
This really helps clarify a lot of things on Xorg.

Cheers
-Rinjo

[David Batson]

I had a mistake in the explanation of the first xrandr command in test 1 above. It has been corrected.

[rinjo]

I had a mistake in the explanation of the first xrandr command in test 1 above. It has been corrected.

No problem
I had understood it in the first place.
Thanks for all ur help.