Problem with video output switching

Affected Models

• ThinkPad T40, T40p, T41, T41p, T42, T42p, T43, T43p
• ThinkPad X41

Problem Description

Problems with Intel chipsets

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

• 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 doesn't seem to allow to change the state of the internal LCD.

• With ibm-acpi, # echo lcd_disable >/proc/acpi/ibm/video works, but # 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 ctrlaltF1 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 known issue of xorgs radeon driver that FnF7 doesn't work.

Related Links

• https://bugs.freedesktop.org/show_bug.cgi?id=2000

Solutions

None (yet).