Trying to upgrade the graphics card for my 2017 iMac to get better export and rendering times. Any suggestions on which of the compatible graphics cards to choose for my Razer Core X - or where to look for more information?
samuelmetzger wrote: Trying to upgrade the graphics card for my 2017 iMac to get better export and rendering times. Any suggestions on which of the compatible graphics cards to choose for my Razer Core X - or where to look for more information?
Export consists of two phases: render and encode. In general an eGPU (or any GPU) will not improve the encode phase. If the render phase includes GPU-intensive effects it might improve that. You can check the relative % of each phase by disabling background rendering, deleting all render files, do a one-time manual render of the timeline via CMD+A to select all clips then CTRL+R to render. Time how long the render takes.
After the render, export it and time that. This test will show the % of time spent on render vs export/encode.
If you are exporting to H264, the fastest way is often: File>Share>Master File>Settings, Format: Computer, H.264 Faster Encode, Resolution: 1080p.
Max Yuryev has done lots of testing on various eGPUs, here is one example:
When Mac Pro 7.1 (together a Catalina OS update) were launched last Fall, Apple stated that FCPX and Motion will take advantage of multiGPU Mac computers (due to Metal2). Even though my 2019 iMac 27" has a great Pro Vega 48 I thought that add a second eGPU would be a good idea. I chose an OWC eGPU external chasis (sales) and I bought a Radeon Vega 56. Today I think was a right choice
I have not done before/after tests because of I bought the iMac just when Apple updated FCPX and Catalina. But I can say that FCPX is able to use both internal/external GPU (as you know you can check the eGPU in render/share playback preferences). I don't know the total impact about renders time on your specific computer, but I think that you must also notice a substantial improvement