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    T400s not using C6 C-state

    Discussion in 'Lenovo' started by mintcoffee, Sep 22, 2009.

  1. mintcoffee

    mintcoffee Newbie

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    Im running Linux on my T400s and I noticed that in powertop, the available C-states are only C1 through C3.

    Here's the output:

    Your CPU supports the following C-states : C1 C2 C3 C4 C5 C6
    Your BIOS reports the following C-states : C1 C2 C3

    This doesn't change depending on whether I'm on A/C or battery power. I've tried tweaking the BIOs options for the CPU and managed to get C4 state enabled when selecting 'Automatic' when on A/C power. However, there doesn't seem to be a way to configure the states for battery power. Anyone else notice this?
     
    mintcoffee, Sep 22, 2009
    #1