Nouveau Works On Optimus Dynamic Power Handling
Written by Michael Larabel in Nouveau on 2 August 2013 at 03:58 AM EDT. 6 Comments
While DRI2 PRIME has led to Optimus-like support for laptops with NVIDIA/Intel GPU combinations, one of the problems making this technology less beneficial is the lack of dynamic power management handling. What's the point of keeping one GPU fed with power when it's being unused and just lowering your battery life? Fortunately, a fix is ahead.

David Airlie published this week patches to provide Optimus dynamic power off for the Nouveau open-source NVIDIA driver. This work requires changes to VGA Switcheroo, the Nouveau DRM, and the HDA_Intel audio driver for turning off power to the secondary GPU in Optimus laptops. This obviously saves a lot of power not having to keep the second GPU powered on when it's not even being used at the moment for rendering.

If the patches work well, the secondary GPU should then power back up when it's needed, whether it means when running commands like lspci or using DRI_PRIME for offloaded rendering. No manual intervention on the behalf of the end-user is required.

Aside from NVIDIA Optimus laptops, this work is also intended to help MUX-less AMD PowerXpress laptops too, but right now just the Nouveau driver is implemented. Sadly though this isn't related to any improvements with regard to dynamic re-clocking for better allowing NVIDIA GPUs controlled by the Nouveau driver to better re-clock dynamically to their highest performance states.

The current patches for this Nouveau Optimus dynamic power off support can be found on the dri-devel mailing list and will hopefully be merged into an upcoming Linux kernel release, at the earliest it would be the Linux 3.12 kernel.

About The Author
Author picture

Michael Larabel is the principal author of and founded the site in 2004 with a focus on enriching the Linux hardware experience. Michael has written more than 10,000 articles covering the state of Linux hardware support, Linux performance, graphics drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and automated benchmarking software. He can be followed via Twitter or contacted via

Related Nouveau News
Popular News
Trending Reviews & Featured Articles