GeForce 830M and NvEnc support

Hi! Please tell me something about this - GeForce 830M is based on the Maxwell chip GM108, Windows 10 (but I tried the same on Windows 8.1). I installed CUDA 7.5 SDK and NvEnc 5.0.1 SDK. I tried NvEncoder sample but it doesn’t work. The call “nvStatus = m_pEncodeAPI->nvEncOpenEncodeSessionEx(&openSessionExParams, &m_hEncoder);” always returns NV_ENC_ERR_UNSUPPORTED_DEVICE (0x00000002) error. On the video SDK web-site “” there is the following text about GPUs:

NVIDIA Quadro K4000 and above – Desktop Workstation
NVIDIA Quadro K2000M and above – Mobile Workstation
NVIDIA Tesla K10 and above – High Performance Computing
NVIDIA GRID – Virtual Desktops & Applications
NVIDIA GeForce - and all others not in the list above (Kepler and Maxwell GPUs) - Desktop and Mobile Computers – limited to 2 encode sessions per system

so GeForce 830M should be supported because it has Maxwell GPU. I tried D3D9, D3D10, D3D11 and CUDA for device type but none of them works. One thing is different between CUDA and D3D devices - in the output window I can see a message ‘D3D11: Removing Device.’.

And I tried NvEnc SDK 4 but also failed. The log is the following:

[i]>> GetNumberEncoders() has detected 1 CUDA capable GPU device(s) <<
[ GPU #0 - < GeForce 830M > has Compute SM 5.0, NVENC Available ]

InitCUDA() has detected 1 CUDA capable GPU device(s)<<
[ GPU #0 - < GeForce 830M > has Compute SM 5.0, Available NVENC ]

Select GPU #0 - < GeForce 830M > supports SM 5.0 and NVENC
File: src\CNVEncoder.cpp, Line: 1873, nvEncOpenEncodeSessionEx() returned with error 2
Note: GUID key may be invalid or incorrect. Recommend to upgrade your drivers and obtain a new key[/i]

How I can resolve this problem? Perhaps I need some kind of a special driver?

NVidia support was unable to answer. Thus I returned the laptop to the seller. The question is not actual anymore.