Comment 15 for bug 818830

same problem here on the x220i (oneiric 32bit). the combination of both
settings work for me too, battery usage went down from 15 to 8 watt!
On Oct 16, 2011 1:30 AM, "hanfkeks" <email address hidden> wrote:

> same problem here,
> pcie_aspm=force acpi=noirq
> or
> i915.i915_enable_rc6=1
>
> by itself didn t do any good, but in combination it helped me on a
> oneiric amd64 on my Thinkpad X220i with an i3.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/818830
>
> Title:
> [Sandy Bridge] serious power regression from kernel 3.0.0-6 to 3.0.0-7
> (rc6 disabled)
>
> Status in “linux” package in Ubuntu:
> Triaged
>
> Bug description:
> On Ubuntu Oneiric, I discovered a serious power regression from Kernel
> 3.0.0-6-generic to 3.0.0-7-generic.
> It is on an Intel Sandy Bridge Laptop. Unplugging the laptop from ac power
> source I made the tests without any graphical user interface active with the
> same brightness and other settings. When I boot into the kernels I have the
> following idle power numbers with
>
> grep rate /proc/acpi/battery/BAT0/state:
>
> - Kernel 3.0.0-6: present rate: 1530-1560mW
> - Kernel 3.0.0-7: present rate: 1950-2020mW
>
> It is a more than 30% (!!!) increase in power usage withe the same hw,
> same settings, different Kernel version.
> Which is really annoying as the laptop fans start working above
> 1700-1800mw, so it is night and day in usage comfort the laptop with the two
> kernels.
>
> Here is the kernel log for both versions:
>
> Log with 3.0.0-6: http://pastebin.com/e0UER3zf
> Log with 3.0.0-7: http://pastebin.com/5JcrZ5Br
>
> Please let me know if you need any more data on this.
>
> The problem is 100% reproducible.
>
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>