Operating a laptop when closed. Disabling the lid switch ?

[Tim]

On Thu, 2012-01-19 at 19:08 +0100, Reindl Harald wrote:
> you do not really want this because the machine will OVERHEAT!

*May* overheat...

It depends on the design of the laptop's ventilation.  Some depend on
vents around the keyboard, that will be blocked off by the screen.
Others have ventilation that uses grills in the bottom and/or the sides.

Some laptops can run cooler with the lid down.  Why?  Because they can:

 * Turn the screen off, or into low power mode.
 * Turn the graphics chips off, or into low power mode.

Neither need to be on when there's no display visible.  

Running a laptop with an external display may be a cause for heat
generation from the graphics chips, they may not be the same chips used
to drive the internal display.

Monitor the temperature when you try this.  Listen to the fans, notice
if they speed up (to force more cooling).

-- 
[tim at localhost ~]$ uname -r
2.6.27.25-78.2.56.fc9.i686

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