Here is proof that the latest update to FCPX is slower than the previous 10.4.6 on my Mac Book Pro with both rendering and playback and shows how the eGPU use is less utilised and slower than in 10.4.6.
Macbook Pro 15 Inch Late 2016, 2.9Quad i7, 16GB ram, 2TB SSD, Catalina
eGPU: Radeon vii in Razor Core X
I ran exactly the same test on 10.4.6 and 10.4.7 both with and without eGPU connected
[Playback: 1st playback playing through same rendered & unrended clips
2nd playback down after the first run playing through same rendered & unrended again]
Render two clips from Canon 5DM4 4K:
(1) 10.4.6 without eGPU 3:10min [1st Playback both no lag, 2nd both small lag]
(2) 10.4.6 with eGPU 3:50min [1st both no lag, 2nd no lag]
(3) 10.4.7 with eGPU 4min [1st rendered smooth, un-ren. laggy, 2nd both laggy]
(4) 10.4.7 without eGPU 4min [both no lag, 2nd both laggy]
Render two clips from RED Raw R3d 5K:
(5) 10.4.6 without eGPU 2:55min [1st rendered smooth, un-ren. laggy, 2nd both laggy]
(6) 10.4.6 with eGPU 2:50min [1st rendered smooth, un-ren. laggy, 2nd rendered no lag, un-ren lag]
(7) 10.4.7 with eGPU 3:58min [1st both laggy, 2nd both laggy]
(8) 10.4.7 with eGPU 3:05min [1st rendered smooth, un-ren. laggy, 2nd both laggy]
Findings are clear that FCPX 10.4.6 is faster in both rendering and playback than 10.4.7 and its better WITHOUT an eGPU on both compressed and uncompressed video. The best setup overall was 10.4.6 and no eGPU.
Most interesting is (3) which happens to be the worst overall, which I had expected to be the best. A very powerful eGPU with the latest update of FCP 10.4.7. It doesn't even use the eGPU at all barely!!? I read on this 10.4.7 update how they were advertising improved eGPU use?
If wish this information was available before I bought Final Cut Pro X as I moved from Premiere Pro and bought the eGPU for this specific purpose. So hopefully this helps those considering buying an eGPU to use with their Macbook Pro and FCPX. Final Cut is faster and smoother in playback than Preimere Pro in both compressed video [Canon] and especially with RED footage. Just don't bother with an eGPU at this stage.
Would love for others input and ideas as I'm not much of a tech person, I just needed to know for myself if I had wasted all this money or not on an eGPU. For me the most important thing is playback and secondarily rendering. I don't really care for export as I can always do that overnight if needed. I wanted to be able to edit on MacBook Pro and just plug in eGPU when needed without buying a whole new system. I've read on these forums people saying that playback is more CPU than GPU but my main argument was that 10.4.6 was faster than the old one with playback, and now this proves it with my system.
Please let me know if I've got anything wrong or there or other ways I can speed playback up, or if there is going to be something done in the future to improve this. My guess is that 10.4.7 is built to be faster on the new Mac Pro etc and I'm sure it will be, this information is for those using current systems.