HP/Compaq :: To Hack NC4200 LCD Ambient Light Sensor

I have the business HP NC4200 laptop, which has a great ambient light sensor.

I generally disable it, because the screen gets too dim in nearly every situation, in my opinion.

But I noticed something strange. When the ambient light sensor is disabled, it is possible to adjust the screen's brightness at your own taste. This is logical.

But you cannot get the screen to 100% brightness. The only way to get 100% brightness is to actually ACTIVATE the ambient light sensor and get a very bright light source right into the ambient light sensor. Then the screen gets MUCH brighter.

Don't bother saying, I've used the Fn keys to control the LCD brightness. That's they way it works.

I use notebook hardware control, and with the nc4200 I can monitor the power consumption of the system in Watts. When the screen is maxed out without the ambient light sensor (which is approx. 50% of the LCD brightness, in reality) the system consumes around 10 watts of power.

When I max the screen with the trick mentioned above, the screen consumes +2 Watts! No need to mention battery life drops a lot.

But I do like that brightness! I'd like to keep it all the time. But it's impossible to apply the trick all the time..................