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I've recently installed Ubuntu 11.10 on a new Lenovo X220 laptop with a 9-cells battery. I have a trans-atlantic flight coming up, and I would like to use my laptop during it. Lenovo claims that this battery should last for a really long time.
How can I configure my laptop to consume minimal power? I didn't see any detailed power management panel in the system settings, so how to I tweak it?
Also, can someone report a tried-and-tested configuration? Performance is not an issue, since I'm going to use it for coding or reading during the flight, not for playing games of watching movies. Playing audio would be nice, but not a must.