I'm having this problem for quite some time with all of my projects. When I'm trying to render an image or animation (I'm rendering with GPU only because it's the fastest way for me), the beginning gets rendered really quickly, but after a short time later (when the render is finished at 15%), the process becomes really slow, until the end. I have posted details about my machine and the reference photo too below:
- Processor - Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz 260GHz;
- RAM - 8.00 GB (during rendering, it only uses ~500 MB);
- The program is installed on SSD disc;
- Windows 10 Home 64 bit (version 1809);
- GPU - NVIDIA GeForce GTX 1650 6 GB.
As you can see, very little of the GPU is used, which is why I think the rendering is slow...