New CPUs with Sandy bridge technology have integrated graphics processing units (APUs), which enables manufacturers to add another graphics card which is much more powerful and let the user switch between 2 graphics cards. One for battery preservation or both if you favor power.

In Windows 7 environment Nvidia Optimus GPU switching works nicely - switch to Power saving mode to shut down the GPU, switch to High performance to enable both GPUs. However, I recently installed Ubuntu 10.10 and was disappointed to find out that Nvidia Optimus does not work on Linux and they don’t have any plans to support it on Linux (Nvidia officials actually wrote that on their support forums). Not only you can’t switch it or use it at all (yet), but there’s no easy way to disable it, so it consumes precious battery power even if you’re not using it. Well, you might be lucky, because some laptops may have a BIOS switch, but if you’re like me and not so lucky - BIOS won’t help here.

And here comes the community to the rescue. Linux Hybrid Graphics is developed by the community, they are rapidly developing software for hybrid graphics cards support on Linux. At the moment of writing this post only a program to disable the NVIDIA graphics card is available. You can find the code here: http://github.com/mkottman/acpi_call

You can install the program with these commands: git clone http://github.com/mkottman/acpi_call.git cd acpi_call make sudo insmod acpi_call.ko ./test_off.sh

I tried it myself, it worked as a charm. My battery life increased more than twice!

I hope it helps.