Watch Power Management in action.
Tired of your laptop dying when you need it most? Windows 7 is designed to help your battery last longer.
How? For starters, Windows 7 runs with fewer background activities, so your PC processor does not work as hard, and draws less power. Other innovations include less power-hungry DVD playback (handy on long flights), automatic screen dimming, powering off unused ports, and a more accurate battery-life indicator. So you will be less likely to be surprised by a dead battery.