Problem with video blanks after lid close and open
- ThinkPad X41
With Intel_Graphics_Media_Accelerator_900, After closing and opening the lid, a short flicker of the display appears, and then the picture disappears with the back light remaining on. The image is directed to the external VGA port, and a CRT connected to it will show the image. Using i810switch (as can be seen here: Problem_with_video_output_switching#Problems_with_Intel_chipsets) the external display will either blank or work again, but the internal LCD remains blank until X restarts. This is caused by an incorrect resume operation of the Intel device, which results in disabling the internal (B) channel and enabling the external (A) channel. This behavior was noted on Ubuntu 7.10 and 8.04.
Add section to the xorg.conf file:
Section "ServerFlags" Option "noPM" "true" EndSection