CUDA fails to initialize on iRay and V-Ray (In-process)

[RobH2]

I've had two remote sessions with Chaos Group now in an effort to diagnose and fix CUDA issues on my machine. iRay will not use CUDA, only CPU. V-Ray will use CUDA but only if I disable 'In-process' in the Render Dialog. 

Chaos says this is an Autodesk and Max issue and that they can't do anything about it. They've written a workaround in V-Ray 3 that allows you to uncheck "In-process' so the CUDA initialization doesn't crash Max when it fails. 

Is anyone else experincing this and if so, have you workeded out a solution with Max tech support?

SYSTEM: Active Shade renderer is changed to V-Ray RT 3.30.05. Previous messages are cleared.
SYSTEM: Active Shade renderer is changed to NVIDIA iray. Previous messages are cleared.
IRAY 0.5 58 MB warn : filtering is unsupported for rgba_fp FB_NAME_MAIN
IRAY 0.5 62 MB error: CUDA device 0: cannot get memory statistics (all CUDA-capable devices are busy or unavailable)
IRAY 0.90 87 MB error: CUDA device 0 (Quadro K5200): device kernel image is invalid (Failed to get function attributes)
IRAY 0.90 87 MB error: CUDA device 0 (Quadro K5200): all CUDA-capable devices are busy or unavailable (while allocating host mapped memory buffer)
IRAY 0.90 87 MB error: CUDA device 0 (Quadro K5200): device cannot be used as it does not support mapped memory (canMapHostMemory)
IRAY 0.90 87 MB error: CUDA device 0 (Quadro K5200): Device initialization failed, will not be used
IRAY 0.5 109 MB warn : filtering is unsupported for rgba_fp FB_NAME_MAIN
SYSTEM: Active Shade renderer is changed to NVIDIA mental ray. Previous messages are cleared.
IRAY 0.11 66 MB warn : filtering is unsupported for rgba_fp FB_NAME_MAIN
IRAY 0.11 67 MB error: CUDA device 0: cannot get memory statistics (all CUDA-capable devices are busy or unavailable)
IRAY 0.93 91 MB error: CUDA device 0 (Quadro K5200): device kernel image is invalid (Failed to get function attributes)
IRAY 0.93 91 MB error: CUDA device 0 (Quadro K5200): all CUDA-capable devices are busy or unavailable (while allocating host mapped memory buffer)
IRAY 0.93 91 MB error: CUDA device 0 (Quadro K5200): device cannot be used as it does not support mapped memory (canMapHostMemory)
IRAY 0.93 91 MB error: CUDA device 0 (Quadro K5200): Device initialization failed, will not be used

[RobH2]

Thinking that the latest NVidia drivers may have propagated the CUDA malfunction, I went back a few versions and installed an older driver. I tried:

Version:	354.56  WHQL
Release Date:	2015.12.9
Operating System:	Windows 10 64-bit
Language:	English (US)
File Size:	245.21 MB

It did not solve the problem. At some point, I may go back further but that might not be a good solution. Were I to find a working version, it might be so far back that other things would not function properly. 

I just wanted to update the thread.