Revamped ThinkPads claim up to 30 hours of run time
 

The star of the new family looks to be the T420s, which Lenovo provides a few details about. It's "ultra-thin," weighs less than four pounds, features Nvidia Optimus switchable graphics technology, and can purportedly achieve 15 hours of run time with one nine-cell battery and up to 30 hours with a second, nine-cell "slice" battery. Impressive if true... although published battery life ratings are usually a tad over-optimistic.

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