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If i with

dmesg | grep -i aspm

have this:

[    0.503709] ACPI FADT declares the system doesn't support PCIe ASPM, so disable it
[    0.673564] ACPI _OSC control for PCIe not granted, disabling ASPM

I've read that is a bug in the Linux kernel and I've also read that there is a workaround but I don't know if I have to apply this workaround or not.

So do I have to add pcie_aspm=force to grub2?

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see similar question:… – fossfreedom Oct 11 '11 at 17:36
Have you solved this issue? – pl1nk Jun 27 '12 at 8:12

Ok, i've add "pcie_aspm=force" and i've gained 20 minutes :)
So if someone have a Sony Vaio VPC-EH1S0E can easily add the parameter to the grub line in this way:

sudo nano -w /etc/default/grub

and where there is this line:


change it into:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pcie_aspm=force"

You can also check the power consumption with powertop:

sudo apt-get install powertop

and then:
sudo powertop
My battery consumption was decreased from 20.1W to 15.3W :)

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This may work for some, and others have the same problem as me. See this comment:… As you can see, at first they said I was nuts, a week later people asked me if there was any way to fix their batteries. – RobinJ Dec 2 '11 at 12:57

Andrew Wyatt's blog post About the Kernel 3.0 "Power Regression" Myth explains well about kernel regression and aspm issue. May be it would be of some help.

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i've read it seem that i have to add the line to grub right? – Paolo Oct 11 '11 at 7:47
If it says so.. – sagarchalise Oct 11 '11 at 7:57

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