Thunderbolt's future on the Mac could be saved by the USB-C port

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Credit: Intel

Just when you thought Thunderbolt was dead, it comes back to life like a horror-movie monster. On Tuesday Intel announced Thunderbolt 3, offering more bandwidth, trademark Thunderbolt versatility, and a page from the old Thunderbolt playbook–plug compatibility with an existing connector.

The result: On Monday, I was dubious about Thunderbolt’s future as an offered port on all but Apple’s highest-end Macs. Today, I’m guardedly optimistic that Thunderbolt 3 will be the main (if not only) connector on the Mac line in the near future.

Yes, it’s much faster

As Gordon Mah Ung reported earlier on Macworld, Thunderbolt 3 doubles the bandwidth of Thunderbolt 2, to 40Gbps–the original Thunderbolt only supported 10Gbps of bandwidth.

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But Thunderbolt’s appeal has always been its versatility. Like its predecessors, Thunderbolt 3 can connect to ethernet, USB, external video, and high-speed storage. Thunderbolt 3 also can provide power–up to 100 watts–which is good enough charge your laptop (but might not be enough to power, say, a 5K display).

Apple took advantage of Thunderbolt’s versatility when it built the original Thunderbolt Display, which connected to a Mac with a single Thunderbolt cable and provided gigabit ethernet, audio, USB, FireWire, and Thunderbolt. I’ve been using a Belkin Thunderbolt Dock for a while now, and I love it–it provides me with an array of ports while I only need to connect a single cable to my Mac. (It’s especially great for laptop users who want to dock at a desk with a big monitor, wired ethernet, and the like.)

Intel says Thunderbolt 2 can support two 4K 60Hz video displays, which is pretty impressive, and can create incredibly fast networking between two computers at 10GbE (yep, that’s ten times the speed of Gigabit ethernet) for speedy file transfers.

So, Thunderbolt’s pretty great–but with Apple dropping everything but a tiny USB-C port on the new MacBook, and with USB-C itself being pretty versatile, it started to seem like perhaps Apple was going to start de-emphasizing Thunderbolt.

One connector for them all

It turns out that Thunderbolt and USB-C are now allies. That’s because the standard Thunderbolt 3 connector is the USB-C connector. When Mac users first met Thunderbolt, it came in the form of a familiar port shape–namely, Mini DisplayPort. Using that port shape meant that Apple’s systems didn’t need to offer both a Thunderbolt port and a Mini DisplayPort port, because the Thunderbolt port could do either.

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Thunderbolt and Thunderbolt 2 cables fit into the Mini DisplayPort connections Mac users were already familiar with.

A Thunderbolt 3 port will look like a USB-C port. They’re plug compatible. So if you plug in a USB-C device to a Thunderbolt 3 port, it should just work as you’d expect. And older Thunderbolt devices can still be used with Thunderbolt 3 via an adapter.

I’m optimistic that between Apple’s recent use of USB-C on the MacBook and its past embrace of Thunderbolt, we will begin to see Thunderbolt 3 ports on future Macs. While it’s possible that Apple will turn its back on Intel and Thunderbolt, this announcement feels like the sort of technology Apple would want to integrate into its future products, since it joins USB and Thunderbolt into a single port and provides all the versatility that Apple needs. It’s easy for me to imagine these ports replacing all the existing USB and Thunderbolt ports on future Macs.

And now the caveats

If Apple makes a major port transition–no matter if it’s to standard USB-C or to Thunderbolt 3 in a USB-C wrapper–it’ll mean that Mac users will enter a frustrating period of inconsistency. We’ll all be buying adapters for old products and getting frustrated that our current Mac doesn’t support some whizzy device that only supports USB-C or Thunderbolt.

If Apple does adopt Thunderbolt 3 across its product line over the next year, this could mean that this year’s 12-inch MacBook might end up as a bit of an oddity. Not only does it have the one port, which is odd enough, but it might be one of the few Macs to have a plain USB-C port rather than a fancier Thunderbolt 3 port.

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If new Macs get Thunderbolt 3 ports, the current 12-inch MacBook will be awfully lonely with its “USB-C but not Thunderbolt” port.

There’s also the issue of driving 5K displays. Intel’s announcements about Thunderbolt 3 mention that it supports DisplayPort 1.2, which can drive high-resolution displays, but doesn’t appear to have enough bandwidth to drive a 5K display via a single connection. (It can definitely do it via two cables.) The new DisplayPort 1.3 specification, which is being finalized, is supposed to support 5K displays via a single cable. It would be silly if a brand-new technology like Thunderbolt 3 shipped without the ability to drive 5K displays via a single cable, but that might be the case. We’ll have to wait and see.

Finally, there’s one other catch about Thunderbolt 3 adopting the USB-C connector: Room for confusion. You should be able to plug any USB-C device into a Thunderbolt 3 port without trouble. But if you’ve got a computer (like the new MacBook) that supports USB-C but not Thunderbolt, Thunderbolt peripherals (indicated by the lightning-bolt Thunderbolt logo rather than the USB logo) just won’t work (even though you can plug them in).

In practice, I’m not sure this will be a huge problem. Most hard drives and other simple peripherals will probably just use USB-C in order to maximize compatibility. But some devices, including docks, will require Thunderbolt, and those won’t work on USB-C-only devices like the new MacBook.

Times of frustration

Transitions like these can be frustrating for users. Nobody likes having to buy adapters or looking on at new products with envy because they’re simply not compatible with the computer they bought recently. But in the end, this is how progress happens. Intel’s use of the USB-C connector for Thunderbolt 3 has the promise to make the future a lot simpler and better—but as always, it’ll be a bit bumpy getting there.

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