Follow these steps to increase your laptop's battery life:
Stop your wireless signal when you are not using it.
Can save 20 minutes of your laptop's battery time because WiFi can use a considerable quantity of power. By right clicking on your WiFi connection you can stop your WiFi signal when you are not using it.
Manage the correct power scheme in XP
Windows XP contain a number of predetermined power plans, which control settings like how rapidly your laptop turns off and when your screen saver boots in. You can change your laptop power scheme by choosing Control Panel > Power Options. For max battery life from the "Power scheme" chooses the option "Max. Battery" and decline the list. There are good choices for you just like "Low Power Mode" and Portable /Laptop. They don't conserve as much power as Max Battery. After selecting a power scheme you click Ok button to finish the process.
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