The tests were performed in a newly installed Windows XP Professional operating system with a necessary minimum of installed programs. The wireless adapters were disabled, and the “portable/laptop” power management scheme was selected in which we prohibited to turn off hard drives and the monitor and to enable the screensaver and the standby mode.
The screen brightness was set at 120-130 candelas per sq. m by means of a luxmeter for the battery life tests. This allows for better comparison than if we tested at the maximum screen brightness alone (the battery life measurements at the max and min brightness of the screen are also listed in the tables below).
We limited ourselves to two tests only due to the time restrictions (we could not keep some notebook models in our lab for more than a couple of days). These are PCMark 2004 that helps to evaluate the overall performance of the notebook as well as that of each of its main subsystems, and Battery Eater Pro 2.50 that measures the time of autonomous work in two modes (Reader’s and Classic), the difference between which shows the efficiency of the power management system setup of each notebook.
We didn’t run PC Mark when the notebooks were powered by their batteries because with the portable/laptop power management scheme selected the notebook automatically yields its full processing power when necessary and the results of the tests do not depend on the power source. Roughly speaking, the system settings in the Classic mode correspond to the settings of the Always On scheme, and in the Reader’s mode to the Max Battery scheme.