M4400 RGB LED display power consumption

I have been playing with my new M4400 with the RGB LED display and had a watts up connected to the AC outlet. I was testing different power conditions such as express charge and not, full load, ect. Then I tried brightness of the screen at full and min and then off. From the wattage change it looks like the screen consumes somewhere around 14 watts from off to full. That seem like a ton for an LED screen. This is on par with the spec sheets but I figured this spec was the dual CCFL.

Spec: Typical power consumption
(panel with backlight):

WXGA: 6.2 W (max.) with no inverter
losses

WXGA+: 5.8 W (max.)
WUXGA: 13.0 W (max.)

Has any one actually seen the inside of one of backlights on one of these displays, could they really be consuming this much power?

 

The RGB-LED screen uses the most power of all displays, because it uses 3 times the LED quantity of a normal LED screen (actually the same amount of LED for each primary color (red, green, blue)).

Therefore the correct order is:

WXGA (ccfl): 6,2W
WXGA+ (LED): 5,8W
WUXGA (2xccfl): 13,0W (~2x ccfl)
WUXGA (RGB-LED): 15.8W (~3x LED)

 

I just would have though that the dual CCFL would be more power hungry but I guess I was mistaken. I need to try doing some battery life tests, I have been way too tethered to my desk to appreciate my new laptop. Any chance that 15.8 is the dell rated number you found?

 

I first thought the manual is wrong with the power consumptions, but I meassured the consumption with my M6400/RGB-LED and it was about 15W difference between the highest and lowest brightness setting.