Nvidia optimus questions

[peapa]

Hey all

I will potentially buy a Nvidia optimus enabled notebook, but was wondering a few things :

Is the Nvidia GPU powered up under Linux ? I know I won't be able to use it, so i don't want it to eat the battery for nothing...

If it is, is it possible to turn it off using vga_switcheroo ? airlied assumed here that the power up and down part should not be very different between the "old" method and optimus, but I would like to know if anyone already tried (in case the nvidia GPU is powered up).

Google didn't help me so far, I hope you will be able to !

Thanks !

[avilella]

Once the PRIME gpu-offloading code gets implemented, we should have hot-switching capabilities in linux, but right now these are restricted to the type of switching shown in the vga_switcheroo videos.

There is a new acpi_call module that allows calling acpi methods from a running Linux session. Most BIOSes have methods to switch on/off the discrete graphics card, and these can be called in Linux.

For more info, see http://linux-hybrid-graphics.blogspot.com/

Hey all

I will potentially buy a Nvidia optimus enabled notebook, but was wondering a few things :

Is the Nvidia GPU powered up under Linux ? I know I won't be able to use it, so i don't want it to eat the battery for nothing...

If it is, is it possible to turn it off using vga_switcheroo ? airlied assumed here that the power up and down part should not be very different between the "old" method and optimus, but I would like to know if anyone already tried (in case the nvidia GPU is powered up).

Google didn't help me so far, I hope you will be able to !

Thanks !

[peapa]

Okay, so I finally bought the laptop (Asus N61JV), and by using the acpi_call module as you suggested I was indeed able to turn off the unsused nVidia GPU.
It reduces the idle power consumption of the laptop by 25% !

Thanks for pointing me this avilella !

On a side note, this laptop works quite fine with Linux. The only problem I've encountered as of now is that Debian could not use the network card, and it even made it disappear in Windows. Removing the power cable and the battery did the trick to get back the card. My customized Gentoo kernel did not cause any trouble though, so it shouldn't be too hard to troubleshoot this (I was even able to start and use Debian with my Gentoo-compiled kernel)
Otherwise, most of the media keys are working out of the box.
I didn't try using wireless yet, but the chip is recognized by the kernel so setting this up shouldn't be too difficult either.

There is another thing you need to be aware of, which isn't related to Linux : this notebook doesn't have the USB 3 port that is advertised everywhere, so be carefull if you buy it specifically for this feature.
My precise model is N61JV-JX026V, bought in Europe (France).

That's it, if anyone is interested in more informations about this notebook, I'll be happy to answer !

[peapa]

Well, to be more precise about the USB 3 port, the ASUS support told me that it's an option thus it's not present on all models despite being advertised by most (if not all) vendors.