18. Batter Life In Games, Presentations, And DVD Playback

The operating times when running on batter power are based on three typical daily applications:

For all three tests, we used the energy setting "Portable/ Laptop."

One thing becomes immediately apparent: the Pentium-M system runs longer. In order to estimate approximately how much longer it runs compared to the Pentium 4-M notebook, however, the batter capacity must be considered as well. The capacity of the battery in the Pentium-M notebook is 48.8 Wh, while that of the Pentium 4-M battery is about 59 Wh.

If you then take the operating time of both platforms with respect to battery capacity, figuring in a factor of an imaginary battery with a capacity of 10 Wh for example, then the Pentium-M system gives you an operating time of about 20 minutes longer. Sensibly enough, you take the operating time for the presentation application in order to make the calculation: in this operating mode, the optical drive is not in use and the graphics card is not under a heavy load. Therefore, the power consumption of those two components only has a marginal effect on the test results.