Unfortunately I'm busy with RL stuff and that will not change in the near future, so I'm not available to offer a lot of help. Some thoughts on the matter:
1) The OpenCL driver is included in the Nvidia drivers, so that shouldn't be the problem. In addition, from the stderr txt, it's clear that the app sees the GPU as an OpenCL device.
2) I'm not as familiar with OpenCL as I am with CUDA, but there are environmental conditions (e.g., using Windows Remote Desktop) that could cause the GPU to be unavailable. Perhaps something similar is happening here.
3) Do any other OpenCL programs work on your GPU? wwwwcl.exe (userd for WSS and Wieferich on PRPNet) is also an OpenCL app.
I can't guarantee when, or if, I'll be available for followup answers.
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