I have been following the development of Blender and Metal over the past few months and was excited to see that with Mac OS release of 12.3 that Metal would be supported with older Intel Macs with AMD graphics cards. Before I installed 12.3 on. my 2017 5K iMac I ran some benchmarks on a simple Blender scene and some rather strange results.
On OS 12.2.2
Blender 3.0. 45.55 seconds
Blender 3.1b 49.18 seconds
Blender 3.1 today release 49.88 seconds
OS 12.3
Blender 3.1 today release without GPU support 52.23
Blender 3.1 today release with RX580 GPU support 2.15.45
The strange thing is not only is it significantly slower using the Metal but when a start a render I just a spinning lollypop and under force quit it says blender is not responding. If I wait long enough the window will open and the render will complete and reflect to actual total time even including window not open time.
Bottom line here Apple and Blender still have some work to do to implement Metal in Blender.
I’m using a W6800X Duo and it screams in CyclesX. Renders three times faster than my 24-core processor. If Blender/Apple can squeeze even more out if it I’ll be very happy!
I will also say, GPU rendering on cards with only 8GB has proven really flaky for me in the past. I used Octane with C4D and it was a coin toss whether it would crash. As soon as I updated to the 16GB GPU, it rendered much more smoothly and was pretty much crash-free.
Yep, two separate cards (and also the 5700XT I have to drive the monitor). Turn one off and the render times are doubled. Weirdly, I get faster speeds if I don’t include the CPU in the render calculations!