Yes, I said!
What is rendering?
Basically it's the act of your computer calculating all the rays of light that you have in your scene, where they will hit and which will be reflected and where will be reflected, the intensity of these rays and the intensity of the reflected ones, the shadows, etc!
According to the Motherboard's configuration (note that I'm not a hardware technician, I'll just explain this in the most basic way I understand), the communication between the GPU and the CPU is done through some channels, which, if I'm not wrong, it's called Bridges or something like that!
It is necessary that the GPU communicates to the CPU in real time, which pixels it is calculating and the result of that calculation, so that the cpu does not calculate them, and vice versa!
These bridges have a limit of information that they can travel through for a certain time!
As the information is immense, it works like a traffic queue on the highway, on a day of accident, fast away from the crash, but then very slow near it!
You can always take the test yourself and draw your own conclusions, just like I did!
Sometimes we start a render and we get the feeling that it is moving very slowly! This has already happened to me and I stopped the render, went to the rendering options and verified that both options were activated, GPU and CPU! For some reason it activated itself!
It can also happen that your scene has exceeded the capacity of your GPU, in your case 12GB and automatically it has triggered the rendering only by the CPU, but still with GPU checkbox triggered!
It happened to me too!
All this that I told you may be that it only applies in DAZ due to the rendering method used in IRAY by DAZ, which seems to me that it does the total rendering in one go!
In blender, for example, it seems to me that the method used by the Cycles rendering engine has a different way of being done, not doing everything at once, but subdividing by sections! Perhaps there, the joint rendering method already has another result, since it automatically allocates the section that each of them (GPU and CPU) will render and therefore, there is no exchange of information between them!
See the example how Cycles rendering engine works in Blender
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It renders by sections, not all at once!
Jesus, the eyelashes and the Eyebrows stayed on the floor, hihihi!
Daz to Blender bridge at it's best!
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