https://bugzilla.kernel.org/show_bug.cgi?id=57831
--- Comment #3 from Alex Deucher alexdeucher@gmail.com 2013-05-09 21:01:41 --- No both drivers need the vbios image. The closed driver either gets the vbios via some alternative means or it has some sort of fallback image if it can't find the actual vbios image.