How to make use of Power Management features

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Revision as of 12:19, 13 March 2005 by (Talk) (APM vs. ACPI)
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General Information about Power Management features

This page should give you all the information you need to make use of your ThinkPads Power Management features under Linux and hence effectively enhance your battery life.


All ThinkPads support APM and a lot support ACPI as well, but at different qualities of implementation. Both technologies cannot be used simultaneously. So you'll have to make a choice which would depend very much on the model as well as on the state of ACPI support in the kernel.

On older models you are surely better off with APM, if they feature ACPI at all.

It seems that at least in recent models from the A, G, R, T and X series ACPI generally works fine and is a lot more flexible than APM, but with a lot of them also a Problem with high power drain in ACPI sleep has been experienced.

Please check our APM vs. ACPI success table to find out about APM and ACPI support in specific models.

On the other hand simply switching from APM to ACPI extended my X31 battery runtime from about 3.5h to 4h. This had nothing to do with Dynamic Frequency Scaling which was active in both configurations.

>(TODO: more precise and extended info should be provided here)<

How to enable certain features

The following links will take you to separate pages dealing with the various topics.