From what I remember last time I looked into this there is a tradeoff between using CPU and GPU rendering. GPU is usually faster, whereas CPU produces better quality. See this question for more details: https://video.stackexchange.com/questions/14656/why-processo...
For previewing and playing, I use GPU only. For rendering (export), it's a combo of GPU + CPU, and I defer that to Windows - in a nutshell, there's an API that you call, in order to export an .mp4 file. Of course, there's a lot more than that, but you don't control what the OS will use in order to write the .mp4 file.
Yeah heard about that, definitely times in a professional situation you want to be aware of these tradeoffs and be able to make a call depending on your situation.
For previewing and playing, I use GPU only. For rendering (export), it's a combo of GPU + CPU, and I defer that to Windows - in a nutshell, there's an API that you call, in order to export an .mp4 file. Of course, there's a lot more than that, but you don't control what the OS will use in order to write the .mp4 file.