vinegarshots
macrumors 65816
Jesus, the difference in speed is just... wow, ridiculous. On the OpenCL part, you mean the OpenCL version when it was still supported it was even slower than today’s Cycles CPU-mode?
Yes, that's correct. I found a post on the Blender Artists forums from another person who had a similar experience as me (post is quoted below):
"I just did the same test on an iMac Pro at my local computer store. My computer at home is the first edition iMac 5K (so four years old), which I got before I planned to get into 3D (but I did get the best available GPU for it). At home the BMW render took 5 minutes on the CPU, 50 minutes on the GPU. On the iMac Pro it was 4 minutes on the CPU, 15 minutes on the GPU. Something doesn’t seem quite right. On the other hand, there is the AMD ProRender plug-in for Blender, which should work better, although I didn’t get the chance to try it out.
I am also told that you can download the latest OpenCL drivers directly from AMD, which surprised me, because I didn’t think you could manually install drivers on the Mac OS (I assumed you had to wait for Apple to release the next version of the OS)."