App developer

On USB-C and Thunderbolt 3

Marco Arment (via Michael Tsai):

While a wide variety of USB-C dongles are available, most use the same handful of unreliable, mediocre chips inside. Some USB-A dongles make Wi-Fi drop on MacBook Pros. Some USB-A devices don’t work properly when adapted to USB-C, or only work in certain ports. Some devices only work when plugged directly into a laptop’s precious few USB-C ports, rather than any hubs or dongles. And reliable HDMI output seems nearly impossible in practice.

Very few hubs exist to add more USB-C ports, so if you have more than a few peripherals, you can’t just replace all of their cables with USB-C versions. You’ll need a hub that provides multiple USB-A ports instead, and you’ll need to keep your USB-A cables for when you’re plugged into the hub — but also keep USB-C cables or dongles around for everything you might ever need to plug directly into the computer’s ports.

Hubs with additional USB-C ports might pass Thunderbolt through to them, but usually don’t. Sometimes, they add a USB-C port that can only be used for power passthrough. Many hubs with power passthrough have lower wattage limits than a 13-inch or 15-inch laptop needs.

After a bit of trial and error, I’ve settled on using the J5 Create USB-C 4 Port Hub with my MacBook Pro, and I’ve had no issues. Connected to my MacBook Pro:

My current setup just works on my MacBook Pro. (Sans the external SSD, I can also connect the USB-C hub to my (Windows) work laptop and be good to go. Skype for Business calls with an Artemis gaming headset is overkill!) However, it wasn’t all plain sailing.

I initially used Apple’s USB-C Digital AV Multiport Adapter, which had several limitations. Firstly, the USB-C port on the dongle is for power only and doesn’t support data. Secondly, when using the HDMI port to connect to an external monitor, its output was limited to 30fps at 4K1.

I’ve had an equally difficult time purchasing appropriate Thunderbolt 3 cables. The Akitio Node came with a 0.5m Thunderbolt 3 which wasn’t long enough for my needs. My first long cable purchase was the 2m Belkin Thunderbolt 3 cable from Apple. The product description:

This 2-meter cable supports Thunderbolt 3 throughput (up to 40 Gbps), 4K or 5K Thunderbolt display connectivity, and up to 60W of charging power to your Thunderbolt 3 devices.

Use this fully Thunderbolt-certified cable to connect to Thunderbolt 3 docks, hard drives, monitors, and more. You can even use it to daisy-chain up to six Thunderbolt 3 devices.

Unfortunately, it refuses to work with my Akitio Node. Despite being advertised as an active Thunderbolt 3 cable at 2m, it appears to be passive2. I’ve now bought a Cable Matters 2m cable and can confirm that it works perfectly.

Thunderbolt 3 and USB-C are far from perfect. They are, however, a significant step in the right direction.

  1. When using USB-C to USB-C the MacBook will output 60fps at 4K. ↩︎

  2. More info ↩︎