Happy with my late 2018 Mac Mini
As a new eGPU user I posted a couple of weeks ago an issue I was having with my late 2013 MBP and a Sonnet Breakaway box detecting the RX 580 but not detecting the Breakaway box. After I was able to resolve the issue with help of this community, I encountered another issue. FCPX would be running very good with the egpu, then after a couple of minutes FCPX would freeze and I would get the Max rainbow circle of death. As soon as I would disconnect the egpu, I would relaunch FCPX and FCPX would work just fine (just not as fast). So I became very frustrated at this particular issue, I bought an eGPU so my work flow would become faster, however; that was not the case. I figured something in the MBP was bottlenecking, so I decided to buy a late 2018 Mac Mini.
I ended up spending the extra cash to upgrade the processor and storage, went with the i7 processor and 500G SSD. While waiting on the mac mini to arrive, I took the time to upgrade the power supply and fan on the Breakaway Box to a 650w power supply, thinking ahead that I want to upgrade the RX 580 to a Vega 64. Once the mac mini came in the mail, I set up my system and started importing all my video footage so I can start a new video project (which I just finished this past weekend). I have to say, I'm very happy with the result and the times I was getting for importing, rendering, and exporting. Disclamer: I have not run any benchmark numbers, my numbers came from working on the current project.
When I import video, I also create proxy videos and optimized media. 30GB of video with optimized media and proxy would of taken 4-5 hours on my 2013 MBP, and my processor would get very HOT. With the 2018 mac mini, I was able to achieve the same 30GB import with optimized media and proxies in just 30-40 mins (the processor did get hot, however it was for a lot less time than the MBP). Rendering and video scrubbing in optimized video was a breeze with the RX 580, no lag. My surprise was with exporting the 23 mins video I had just produced. Exporting something similar on the 2013 MBP with about 20GB total project, would take about 20 mins. Then, I would compressed the file to MP4 using Handbrake, which would take about 45 mins. With the 2018 mac mini I'm getting less 5 mins export from FCPX, then about 15 mins in Handbrake to compress to MP4.
In conclusion, I'm very happy with the performance of the 2018 Mac Mini. I have not tried to use the built in GPU in FCPX, nor will I ever use it, that's why I have the eGPU.
Great to hear you're enjoying the new Mac mini + eGPU! The internal SSD is now a weakness in terms of capacity imo. Thankfully there are four Thunderbolt 3/USB-C ports. I would recommend adding a scratch drive using a 2TB/4TB NVMe SSD via a USB-C 3.1 gen 2. This will give you a lot more capacity at a very reasonable cost. The USB-C 3.1 gen 2 is roughly half the speed of Thunderbolt 3 (10Gbps vs 22Gbps) but costs a lot less ($50 vs $200).
The only issue with USB based SSD its the HUGE CPU overhead. Faster the SSD, higher the CPU usage.
The difference using thunderbolt is night and day.
Not saying they dont have their use (i have them), but if you are trying to use it for scratch while using your CPU for something else, i would work hard to save the extra money and get yourself something over thunderbolt.