At Nerds LTD, we're frequently tasked with determining which hardware is best suited for our client's individual requirements. When it comes to I/O and real-world performance, we've learned there can be a massive variance between manufacturer's claims about their products, and how they perform in real-world situations. For a deep dive into the differences between various USB specs and how they can be misleading, please see our upcoming article on the topic.
Real World Cases
Thunderbolt 3, and it's accompanying OWC dock is unquestionably faster than its USB-C counterpart when many I/O ports are required at the same time, but what about all the other times when a single port is needed in the field? We designed a robust set of tasks to see if there was a statistically significant difference between the two docks the way most people use them most of the time.
Here's what we did
Why 5.23 Gig?
That's the size of MacOS High Sierra
USB-C 5.23 gig transfer between two USB ports on the dock
TB3 5.23 gig transfer between two USB ports on the dock
SD to lightroom [USB-C]
SD to lightroom [TB3]
SD to lightroom [Sandisk accessory]
5.23 GB gigabit ethernet→ USB-C
5.23 GB gigabit ethernet→ TB3
Audition recording MBP jack
Audition recording TB3 [afterwards, we also did USB-C]
1 minute transcoding of iphone HEVC video → PRORES through [USB-C]
1 minute transcoding of iphone HEVC video → PRORES through [TB3]
After hours of testing, we could find no single task, nor an SSD fast enough to slow down the USB-C dock as compared to it's Thunderbolt 3 counterpart. Based on the specifications for USB-C, only way that's possible is with a perfect adherence to spec. That's one of the most impressive results we've ever seen from a series of tests we've conducted. Perfect adherence to spec is frighteningly uncommon.
USB-C / Thunderbolt 3 Dock Single Task Times (seconds)
Get a Thunderbolt 3 Dock if:
You have a 5k display
You only want to plug one cord to your computer
You have a storage array that’s faster than true usb 3.1 g1
You need the ports only found on the thunderbolt 3 dock [listed below]
You must have the fastest possible I/O solution
You have enough money to not care how you spend it.
You need to plug a daisy-chain of Thunderbolt devices into a single port
Get a USB-C Dock if:
You have a single-port MacBook.
You're buying for a team who mostly does one I/O task at a time.
You'd rather spend the money you save on lightning fast SSD storage.
Who Should Care about These Results?
If you're a purchasing manager who needs to buy lots of docks, the price difference between the Thunderbolt 3 and USB-C dock is significant.
If you run a media shop whose workforce primarily needs lots of ports but rarely use more than one at a times.
If you're the kind of person who begins a casual sentence with the word, "technically," we really don't feel like we need to justify the merit of this study to someone like that.
We had a chance to present and discuss our tests with OWC's CEO and founder, Larry O'Connor at NAB 2018. Needless to say, it wasn't news to him that his products performed flawlessly and exactly to spec. "It doesn't surprise me that you found no difference between the two docks during single-task workflows. We didn't skimp on the design."
To simulate a real-world workflow, we used a 2017 15" MacBook Pro attached to an LG Ultrafine 5K Display. To ensure the MacBook Pro wasn't affected by screen recording during our tests, we captured the tasks by recording the MacBook Pro's screen with an AJA I/O XT on a separate iMac and used its SMPTE timecode to make our measurements.
Just for fun, we also tested the recording quality of each dock's front headset port for comparison against the native MacBook Pro port. Since the MacBook Pro's headphone jack automatically boots audio levels, you'll find that the dock's input levels are slightly lower. We tried to normalize the audio a little but there's still a noticeable difference. If you cant hear the difference, download the wave files and look at the waveforms. We've done enough audio production to trust our ears and really can't tell the difference.
OWC's Thunderbolt 3 dock costs roughly twice what its USB-C counterpart does. There's a subtle price break on the mini-display port version of the USB-C dock, but we assume HDMI would be far more useful in the field under most circumstances. OWC also sells a travel dock which wasn't part of our testing.
Background: Why we did this much testing.
While the 2016 and 2017 MacBook Pro support both Thunderbolt 3 and USB-C, many of our corporate clients had upgraded their mobile fleets to the new MacBook Pros only to be told by their employees that their fancy new gear was less useful. The employees claimed the litany of dongles required to get the same industry standard ports required for a typical workflow was a pain. Furthermore, the dongles were expensive, easy to lose, and unnecessarily annoying in the field. As such, these corporate clients wanted to provide what their employees needed while only buying the Thunderbolt 3 docks for the departments whose positions actually benefitted from its additional throughput.
Ports the USB-C Dock Doesn't Have
- HDMI (non-mDP) model
- 1 extra USB 3.1 gen 1
- SPDIF optical audio out
- Firewire 800
We hate long lists of stuff you can simply look up. To save time, here are the ports the Thunderbolt 3 dock has which the USB-C dock does not. For the full list of ports each dock has, check OWC's site.
Corrections & Addendums
We didn't realize that the USB-C dock's front headphone jack also supported microphone audio. While it wasn't part of our initial 11 tests, we're including a Bose headset recording from the USB-C dock for completeness.
Hopefully, our tests will take the guesswork out of deciding between the USB-C & thunderbolt 3 docks. We scoured the web and believe this to be the most extensive set of tests performed on the two products ever. If you have questions, don't hesitate to contact us.
Thanks to OWC for their excellent summary of this article.