https://bugs.freedesktop.org/show_bug.cgi?id=41265
--- Comment #19 from Alex Deucher agd5f@yahoo.com 2012-07-30 13:37:42 UTC --- Where the vbios (video bios) for the discrete card is stored (on a rom on the board, in the sbios (system bios), etc.). If it's part of the sbios, there's probably an ACPI method (ROM or ATRM) to access it.