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I am considering to try what is mentioned here - Battery life decreased after upgrade to 11.04 - concerning minimizing power consumption.

For example I see that in my case - i915.i915_enable_rc6=0 by issuing the following command cat /sys/module/i915/parameters/i915_enable_rc6 .

Would it be possible to switch it to 1 after booting?

If yes, how can we do that?

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You could try something like the following as root:

sudo -i
echo 1 > /sys/module/i915/parameters/i915_enable_rc6
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You can also do:

sudo modinfo i915 | grep "i915_enable_rc6"

You would see this:

    parm:           i915_enable_rc6:Enable power-saving render C-state 6. 
    Different stages can be selected via bitmask values (0 = disable; 1 = enable rc6; 
2 = enable deep rc6; 4 = enable deepest rc6).
    For example, 3 would enable rc6 and deep rc6, and 7 would enable everything.
    default: -1 (use per-chip default) (int)

I think that answers your question : )

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