Problem with video output switching

2006-08-08T23:28:08Z

Pbostley: /* Problems with ATI chipsets */

==Affected Models==
*ThinkPad {{T40}}, {{T40p}}, {{T41}}, {{T41p}}, {{T42}}, {{T42p}}, {{T43}}, {{T43p}}
*ThinkPad {{X22}}, {{X23}}, {{X41}}

==Problem Description==
It is not possible, using the FN-F7 key, to switch between the LCD and the external monitor in the following way
LCD --> external Monitor--> both -->LCD
however ''cloning'' is possible for the Intel chipsets, see below.

===Problems with Intel chipsets===
Disabling the internal LCD (e.g. when using an external Monitor) doesn't seem to work reliably.

* For Xorg 7.022 one can clone the LCD display to an external monitor, adding the following lines to the Device section in the xorg.conf file:
Section "Device"
Identifier "Generic Video Card"
Driver "i810"
Option "Clone" "true"
Option "MonitorLayout" "CRT,LFP"
however you can not switch between these screens as described above, once you use FN-F7 the cloned display is lost.

* i810switch doesn't have any effect. After disabling the LCD it is still on (but the status display of i810switch claims that is is switched off).

* i855crt works see: http://stefan.desire.ch/howto/x41debian/ for details.

* With [[ibm-acpi]], {{cmdroot|echo lcd_disable >/proc/acpi/ibm/video}} works, but {{cmdroot|echo lcd_enable >/proc/acpi/ibm/video}} doesn't work - so one can't enable it anymore after disabling it. (the strange thing is that when switching to a console with {{key|ctrl}}{{key|alt}}{{key|F1}} the LCD display is used for it, so there must be some way to enable it but I can't find out how to control this in X). I've tried this with version 0.8 and version 0.11 of [[ibm-acpi]].

===Problems with ATI chipsets===
*It is a [http://bugs.freedesktop.org/show_bug.cgi?id=2000 known issue] of xorgs radeon driver that {{key|Fn}}{{key|F7}} doesn't work.

You can force the <tt>radeon</tt> driver to enable both CRT and LCD using <tt>Option "MonitorLayout" "LVDS,CRT"</tt> in the <tt>"Device"</tt> section of {{path|/etc/X11/xorg.conf}}. The analogous option for [[fglrx]] is <tt>Option "ForceMonitors" "lvds,crt1"</tt>

The {{cmdroot|radeontool light off}} and {{cmdroot|radeontool dac off}} commands will disable the LCD and CRT if they're been enabled before in the X server, but the corresponding {{cmdroot|radeontool light on}} and {{cmdroot|radeontool dac on}} will not work if the displays have were not enabled when the X server started. Also note that turing off the CRT using this command will not reduce power consumption, nor allow [[fglrx]] to enable power saving modes.

You might try the following: Hit Ctrl+Alt+F1 to switch to a console, hit Fn+F7 to switch video, hit Alt+F7 to switch back to X.

====fglrx-Driver====
Output switching with the Closed-Source ati-driver works: Just use {{cmdroot|aticonfig --query-monitor}} and e.g. {{cmdroot |aticonfig --enable-monitor..."}}. You can use those two commands in a script, and bind them to {{key|Fn}}{{key|F7}}

==Related Links==
*https://bugs.freedesktop.org/show_bug.cgi?id=2000

==Solutions==

====BIOSHotKeys====

Try adding
Option "BiosHotKeys" "on"
to /etc/xorg.conf. For some reason, this is not the default, and will cause xorg to ignore the BIOS's request to switch modes!
This fixes the problem for an X22, with xorg 6.9.0.

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Problem with video output switching