Does Premiere Pro support AMD Radeon Pro W5700X on Mac Pro 2019?

What I am going to state is not just applicable to the W5700X in MacOS, but also to all RDNA-based Radeon GPUs in both MacOS and Windows. The available drivers for both platforms for that series of GPUs still have teething issues.

I can verify it works, however, it's not yet fully compatible. I have a Mac Pro with the Radeon Pro W5700X and I've noticed some strange behavior with Adobe Premiere. Sometimes when I have a video clip with black levels below 0, I get strange colors or red patches in the preview monitor. The video is fine on export, but it's annoying to see this on playback. I could fix this with an adjustment later and the Video Limiter effect, but that's not viable for quick editing and playback. Sometimes when I restart Premiere Pro it goes away but then it comes back. I've not had a lot of time to get to the bottom of this, however, turning off Metal GPU acceleration makes it go away and then turning it back on makes it come back. So there are probably some incompatibilities with this new card, but given how poorly Premiere Pro takes advantage of GPUs in general, it's just the tip of a more serious iceberg. I hope that Adobe will pay more attention to GPU acceleration, in the meantime, it's editing in Premiere Pro but for color grading and effects, at this point in time I do those in Resolve for the performance advantages.

I have a Mac Pro with the Radeon Pro W5700X and I've noticed some strange behavior with Adobe Premiere. Sometimes when I have a video clip with black levels below 0, I get strange colors or red patches in the preview monitor. The video is fine on export, but it's annoying to see this on playback. Then I restart Premiere Pro and it goes away. I've not had a lot of time to get to the bottom of this, however, turning off Metal GPU acceleration makes it go away, and then turning it back on makes it come back. So there are probably some incompatibilities with this new card, but given how poorly Premiere Pro takes advantage of the GPUs, it's not that big of a deal. For basic editing Premiere Pro is fine, but for effects, especially denoising and stabilization and compositing, DaVinci Resolve is a much more efficient tool and it knows how to take advantage of multiple GPUs. I hope that someday Adobe will pay more attention to GPU acceleration, in the meantime, it's editing in Premiere and finishing in Resolve for me.