Thunderbolt 2 fast enough to handle GPU?
I have a iMac 27'' Mid 2014 with only thunderbolt 2. I need a new GPU to handle Davinci Resolve 15 with Raw files.
I was thinking in buying the Blackmagic egpu (Radeon Pro 580) but it only works with thunderbolt 3. I was going to try it with an adapter.
Could this work ?
Any suggestions ?
That should work, though you will have to do some workarounds to get it to work through TB2. I currently use a TB2 enclosure and it works great in Davinci Resolve 15.
The easiest way would be to search the build guides to see if someone did something similar to yours that you can copy.
I just connected a TB2 MacBook (MacBook air 13.3 early 2015 A1466 8GB RAM i5 5250U) to a TB3 enclosure (Sonnet egfx Breakaway 350W) and it works great. I used an apple TB3 to TB 2 adapter plugged into the enclosure and a TB2 cable from there to the TB2 port on the Macbook. I got good benchmarks and it was all plug and play . However, my build is installed on Bootcamp Windows 10 and I'm guessing you want to run Davinci Resolve on MAcOS.
If you look at these throughput specs you will see that you should still get good performance for TB2, TB3>TB2 (16Gb/s), however, I know nothing of Davinci Resolve.
I am using a Sonnet Breakaway Box 550W with PowerColor AMD Vega 64 on my Trashcan Mac Pro. All it took was an Apple TB3-TB2 adapter, TB2 cable and running an enabler script found on this forum. Davinci Resolve Studio 15.3 renders 4K H.264 from ProRes HQ at 12-16fps, 1080p renders in real time. No hiccups on transitions on the Edit page. Fusion clips cause noticeable slowdown, so as noise reduction, as expected.
For most applications TB2 is easily good enough, unless you want to accelerate the internal display.
I am running Sonnet Breakaway Box 550W with PowerColor Radeon Pro Vega 56 flashed to 64 on my trashcan Mac Pro, 3.5GHz, 32GB RAM, dual AMD FirePro D700, using Apple TB3-TB2 adapter. Everything works super smoothly, and I see a significant improvement in Davinci Resolve Studio performance (except, of course, for transcoding H.264, which is a processor-intensive task).
Out of curiosity I decided to see how it will perform on 2017 MacBook Pro 15", 16GB RAM, AMD Radeon Pro 560. The notebook was connected to Sonnet with Belkin 50cm TB3 cable. I expected that TB3 connection will make Vega fly, but to my surprise Davinci Resolve Studio did not seem to work any faster than on the Trashcan. Moreover, it was actually slower.
Knowing that Davinci Resolve Studio uses all available GPUs, I came up with a theory that two D700 GPUs on the Trashcan contributed more than one 560 on the laptop. To exclude confounding factors, I ran Metal Compute tests with Geekbench 4.3.1 on both machines, since Geekbench tests one GPU at a time. Here are the results:
Mac Pro 2013, Thunderbolt 2 165073
Macbook Pro 2017 Thunderbolt 3 142503
Both tests were run without any applications running. Now, somebody tell me that two-fold Thunderbolt 3 performance increase makes any difference...