Vostro 5470 NVidia Error 43 (unsolved)

Hello, I'm time trying to solve the Error 43 problem of off-board nvidia card.

So far I've been through 4 Dell support technicians, have ran numerous websites and forums looking for solution and nothing.

Have tested Windows 7, 8, 8.1 and 10, all x86 and x64.

I also tested the BIOS A09 A10 A11 and A12. It was on the A9 that the board took that breath does not appear the error 43 and was with Windows 8.1 x64, but even not showing error on the card, the Nvidia manager not detect the card, so could not use it. (Not recommend staying changing BIOS, I ventured to do so is dangerous and can damage your notebook permanently)

There are several people in forums and such talking about the same problem, the vast majority managed to solve only updating the BIOS or by downgrading the A12 to A11 or A10. For me no solution worked.

I wonder if anyone has any definitive solution to this persistent problem ...

Thank you!