So I bought the new RX5700 XT card with the Sonnet eGFX Breakaway Box 650 (GPU-650WOC-TB3) to give it a try on my trashcan Mac Pro 2013 and here's the verdict:
I was using eGPU from OWC 550W with a Radeon RX580 on a maxed out cpu/memory trashcan mac pro 2013. It did not offer significant improvements prior to Catalina, but after I updated, wow, what a difference. I thought now it would be a good time to upgrade the video card to get better performance, but was I wrong indeed, as it began dropping frames compared to my old RX580 built. One thing it did better though is rendering time on Premiere Pro, it was significantly faster, but other than that, even the rendered footage showed dropped frames during playback. I tried full resolution playback on 4K files recorded on a GH5 high bit rate 4.2.2 to see how far it could go, and still the RX580 did an excellent job with zero dropped frames.
Good thing my return window is still good so after this failed experiment I will be returning both the RX5700 XT card and the Sonnet eGPU. Funny to mention both the OWC and the Sonnet eGPU are practically identical, the only thing that changes is the front.
Enclosure Photos:
Funny too OWC keeps saying their eGPUs are not compatible with thunderbolt 2 when it works like a charm with purge wrangler script: https://github.com/mayankk2308/purge-wrangler
AMD RX5700 XT may work better on native thunderbolt 3 macs but if you're thinking about updating your cheap old RX580 don't even bother, with Catalina it works great.
Pending: Add my system information and expected eGPU configuration to my signature to give context to my posts
Funny too OWC keeps saying their eGPUs are not compatible with thunderbolt 2 when it works like a charm with purge wrangler script: https://github.com/mayankk2308/purge-wrangler
This is because they cannot diverge from Apple's official standpoint. This is what all vendors will say. However, if you reach out to tech support post purchase, then might link you to the script or automate-eGPU EFI.
Your experience is interesting though. I've recently seen some other posts regarding 5700 XT vs. 580 where the latter was doing better as here. Worth a deep dive - sadly I don't have a Polaris GPU on hand anymore.
I hope RX 580 driver enhancement focused on performance in pro apps is a real thing in Catalina 10.15.2.
If it’s real, maybe fewer people will lol at this:
ﾍ(=￣∇￣)ﾉ
RX580 on Mojave 10.14.6 in MP5,1 performs 15-20% better in GPU benchmarks vs. RX 5700 XT in eGPU (Sonnet 650 OC) on Catalina 10.15.2 on MBP16,1. Real world as much as 33% better for RX580. Catalina has a lot of GPU driver issues. Would not have updated until 10.15.4 if I had the choice, but no way to downgrade an MBP16,1.
Pending: Add my system information and expected eGPU configuration to my signature to give context to my posts