I just made an interesting observation regarding headless displays and maybe also applies for ZenoDiac:

In Windows 10 it happens thst the order of Platforms is volatile when Intel GPU drivers are installed, because with monitor attached or much stress on GPU the Nvida (may also happen with AMD) is platform 0 but without anything platform 0 is Intel and platform 1 is Nvidia. Therefore it can happen that you instead run the Intel iGPU or even CPU when in wrong order.

I will try implementing something that allows auto detection, but currently when platform 0 device 0 is only giving 3 digit sols where there should be more than 5k, then try again with platform 1 device 0. Sometimes this may fix it.