The perfect USB-C dock doesn’t yet exist, but CalDigit’s simply named USB-C Dock ($150; available on Amazon) comes close. The dock, which works with all 2015 and 2016 MacBook and 2016 MacBook Pro models, has a full array of ports, including two different video inputs, as well as high-speed USB charging via Type-A and USB-C jacks. It’s not a cheap option, but it’s reasonably priced for all it offers.
The USB-C Dock’s only significant drawback comes from only supporting under macOS two monitors that mirror one another through its full-sized DisplayPort and HDMI jacks with a 2016 MacBook Pro. You can’t have two external displays act independently and expand the desktop. CalDigit says this is an Apple feature choice, and I’ll explain it and more display details in-depth later in this review.
However, because CalDigit includes DisplayPort and HDMI, you can plug any modern monitor directly without an adapter. You can even use a female Mini-DisplayPort to male DisplayPort adapter, which costs under $10, to use an Apple LED Cinema Display, the version of the display that comes after DVI plugs and before Thunderbolt 2. (The Apple Thunderbolt Display requires a Thunderbolt 3 to Thunderbolt 2 adapter from Apple or a dock with native Thunderbolt 2 ports.)
The USB-C Dock is rather robust on the USB side. The 90-watt dock powers a connected laptop over a provider USB-C cable, which also provides the data link. It includes three USB 3.1 Gen 1 (5 Gbps) Type-A and one USB-C “device” port—one that handles data, rather than laptop-wattage power. It also sports gigabit ethernet, and 3.5 mm audio input and output jacks.
While connected to an Apple LED Cinema Display, I tested SSD write speeds over its Type-A port on both a MacBook and MacBook Pro, and hit the top performance on the drive of over 300 MBps writing and over 400 MBps reading. Its ethernet works as expected.
CalDigit crows a bit in its marketing about two features, one more useful than the other. First, because of its robust DC power supply, it pushes more wattage out of the USB Type-A port on the front of the unit, alongside the audio jacks: it’s a 2.1 amp port, which works out to 10.5W. That allows maximum charging of recent iPhones and nearly top-speed charging for regular iPads. Its USB-C device port maxes out at 3W, allowing 15W charging of an iPad Pro via a Lightning-to-USB-C cable available from Apple.
The second special feature affects only a subset of people, but the dock supports an external CD/DVD SuperDrive reader and burner, which has spotty compatibility among adapters and docks.
CalDigit offers a downloadable extra, which lets you eject all dock-connected hardware with a single menu item, letting you distinguish between drives you may have connected in another fashion. It’s a nice touch.
My only minor cavil is that the aluminum case is a little sharp and industrial to the touch. It’s not bad looking, but it’s more of a throwback to a previous industrial design aesthetic that doesn’t match up as well with modern Mac design.
I should also note that if you want an integrated SD Card slot, which many people rely on for camera media transfers, CalDigit doesn’t have one. As many people have external USB camera card adapters, it’s a terrible omission.
Why only mirroring support for external displays?
CalDigit’s dock supports up to the 4096 x 2160 pixel resolution at 60Hz maximum on the MacBook Pro. But as noted above, it can’t drive two external monitors as distinct displays through its two ports.
The company says that stems from a choice Apple made in implementing multi-stream transport (MST). MST differs from single-stream, in that it allows multiple distinct video desktops to pass over a single connection. This manifests itself both as monitors that combine two streams into a single display, and as adapters like this one that can split two desktop signals to appear on two separate displays.
While Apple says its 2015 and later MacBook Pro models can handle an MST display, handling two displays is off the table for now. CalDigit says a specific MST function called “MST hub” is not turned on in macOS, but believes Apple could enable it later. With Windows, the dock can drive two separate external displays on a capable Windows system.
Thunderbolt 3 docks will bypass this limitation, because DisplayPort is encapsulated inside the Thunderbolt 3 standard over a USB-C connector in a fundamentally different manner, allowing more complicated stream handling. However, Thunderbolt 3 docks with support for two monitors will likely cost $250 to $350.
For now, the option to use either connector type adds flexibility as well as being useful if you have an Apple LED Cinema Display or plan to purchase a used one. If you’re a rare person who needs to mirror a display (perhaps in a classroom), this could fit your needs as well.
MacBook Pro owners can use a second USB-C port or second, third, and forth USB-C port, depending on the model, to drive additional displays as well.
Bottom line
For now, there’s not a better nor more flexible dock you can purchase. It feels a little odd to buy a dock with two display ports for a MacBook Pro when you can only use one of them or mirror two displays, but that’s not CalDigit’s limit. The price stacks up well for competing docks that only have a single HDMI port, and Apple might still unlock more functionality in the future.
For now, it’s the top pick for a full-featured USB-C dock, and will likely remain a good choice for many users even when Thunderbolt 3 docks hit the market because of a lower cost.