Hi Nic - I have been following this forum for a while. I have an ASUS N550VJ. Featuring an intel 4600 and a Nvidia 750m. I have the issue with the Nvidia card showing code43. I tried all combinations of intel drivers and Nvidia drivers, and have tried all Bios' released by Asus. At no point since installing windows 8.1 have I been able to use the Nvidia card as it always reports code43. I have tried downgrading the bios as suggested by ChodeNode - still no luck.
Asus have been very unhelpful with this issue.
Any help on resolving this would be greatly appreciated.
Thanks.