Comment # 46 on bug 75985 from Maik Freudenberg

(In reply to Lukas Wunner from comment #43)
> Is this a Thunderbolt-attached GPU?
Calm down, get back to basics.
This is the dmesg when you turn on the hda dev on a 3d class device.
Just exclude the 3D class from toggling the bit. No big deal.