In newer laptops with switchable graphics, can the high performance card typically be completely disabled?

Question

My laptop is due for upgrade soon and I'm quite keen on the Sony VAIO VPC-CB35FG because of the 1080p display. It comes with Intel/ATI switchable graphics. I use Ubuntu and from what I can tell neither ATI nor switchable graphics in general play very nicely with it. I'm a sysadmin and I don't need high-end graphics at all, so I'm wondering if the high end graphics card in these switchable models can typically be disabled completely?

Answer 1

Typically the answer is "yes", but it depends on the method used for switching. If the graphics system is compatible with VGA_SWITCHAROO, then you can do this at boot time:

 echo IGD > /sys/kernel/debug/vgaswitcheroo/switch
 echo OFF > /sys/kernel/debug/vgaswitcheroo/switch

This says

1. Connect the InteGrateD graphics card to the screen
2. Turn off the other card (the discrete card)

Under windows, the power management usually has an option to enable the discrete card once you are off battery, and you can usually tell it not to do this.

Finally, you can often disable the discrete graphics in the bios.

And post-finally you could open the case and pull the card provided it is a pluggable board, which isn't likely afaik.