Hi Shane,
Thanks so much for the info. I feared that might be the case.
I had seen Mac upgrades like https://create.pro/upgrade, where for about $1,000 I could upgrade to a 12 core processor. And then add better GPU and memory. But if I can’t add Thunderbolt, I guess it’s probably not a good call. iMac Pro for now is out of my price range. I am thinking if / when I upgrade, I may switch to a PC build to to get the most bang for my buck. And from what I’ve read unless I’m tied to Final Cut, a good PC could be the way to go with Premiere.
The good news is that I tested some proxies again, and it might work out. I’m not sure what I did before to make them balloon in size, but my 720p ProRes 422 proxies from H264 4K come out about 1/5 of the size, and they work great. I’ll probably move forward this way for now. And we’ll see what the new 2019 Mac Pro brings with it!
Thanks
Mac Pro (Mid 2010)
3.2 GHz Quad-Core Intel Xeon
16 GB 1066 MHz DDR3
SSD SIERRA 500GB (OS, apps) / HDD 1TB
ATI Radeon HD 5770 1024 MB
OSX Sierra 10.12.6
External Drive: 12 TB (2×6) WD 5200 Raid Duo, USB 3.1
Adobe Premiere Pro CC 2018