Battery operating time can change, sometimes drastically depending on how the notebook is configured and what are attempting to do with the system while only using battery power. Here is a link to the Dell notebook battery FAQ
|Q||How long am I able to use my Dell laptop on a fully charged battery?|
Many factors affect the amount of time that a portable computer battery can deliver power before it must be recharged. These factors include the configuration (processor, memory, etc.), types of applications being run and display brightness.
Dell uses industry standard benchmarks for battery run time claims. For more information on battery run times and benchmarks, the white paper, "Understanding Battery Life in Portable Computers" is available at: <ADMIN NOTE: Broken link has been removed from this post by Dell>
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