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I have dell xps 15 with nvidia 525 with optimus. I use ironhide for optimus support. Under normal conditions I can see 2000+ processor wake ups. As a result of which my battery dries up rapidly. In windows I get almost 4 hours back up and in ubuntu I hardly get 2+ hours battery backup. I'm not able to identify what the problem is. I'm using ubuntu 11.10 32-bit. Please help to resolve my issue.

Thank you

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You can check what processes are responsible for wake ups using gnome-power-statistics..

There is also a tool called powertop which might be of help.

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It sounds like a side-effect of using Ironhide' power management method using ACPI calls (which does not make the kernel aware of device state changes). Bumblebee 3.0 provides more stable power management using bbswitch.

Upgrade from Ironhide to Bumblebee 3.0 following the instructions on

See also: How well do laptops with Nvidia Optimus work?

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