The future of Thunderbolt is USB-C, and this is a good thing

Thunderbolt 3 arrives later this year once computer makers start shipping devices equipped with Intel's "Skylake" microprocessor. Skylake is the successor to Broadwell, the fifth-generation Intel Core processor that saw its debut on the Mac earlier this year. Thunderbolt 3 offers twice the bandwidth of Thunderbolt 2 — up to 40 gigabits per second, more than enough for a computer to drive an external 5K display, for example. Enough to transfer an HD movie from an external hard drive to your Mac in mere seconds.

Apple hasn't announced plans for Skylake yet, but Thunderbolt and Thunderbolt 2 have been important to Apple. Thunderbolt allows the Mac to work with external 4K displays, interface with fast RAID hard drive systems, provide an incredibly fast interface for storage area networks and more. There's no reason to think Apple won't adopt it when the time is right. So I consider Thunderbolt 3 on the Mac an inevitability.

USB-C and Thunderbolt 3 are not the same thing, of course.

USB-C and Thunderbolt 3 are not the same thing, of course. They simply use the same connector. USB-C is the connector; on the MacBook, it's connected to a USB 3.1 interface. So don't think your shiny new gold MacBook is going to work with Thunderbolt 3 devices. On the other hand, any USB-C devices or cables you buy for your new MacBook will work on future Macs equipped with Thunderbolt 3.

This isn't the first time this sort of interface switcheroo has happened, even within the Thunderbolt era. Before Thunderbolt appeared on the Mac, Apple incorporated Mini DisplayPort connectors on some models. Mini DisplayPort is a shrunken-down version of the DisplayPort interface and provides a way to connect external displays without using all the space required for a DVI or VGA port. Physically, Mini DisplayPort looks exactly the same as a Thunderbolt port. The only obvious difference is the logo that appears next to it on the Mac.

USB-C charger

USB-C charger (Image credit: iMore)

Thunderbolt is downwardly compatible with Mini DisplayPort, so if you buy an MDP dongle to attach a monitor or projector, it'll work even on a Mac with a Thunderbolt 2 interface. But if you hook up a Thunderbolt device like a hard drive or a Gigabit Ethernet network interface to a Mini DisplayPort, nothing happens. In the same way, if you hook up a USB-C device or interface adapter to a Thunderbolt 3 port, it'll work. But connecting a Thunderbolt 3 device to a USB-C port that's USB 3.1 won't do anything.

I'm thrilled with this development because as I've written before, I've been plagued by finicky Thunderbolt connections on my Macs. I know many others have as well. The Thunderbolt interface is an imperfect technology, at best. By contrast, my experience with the MacBook's USB-C connector is that it's a solid plug that doesn't easily unseat or jiggle loose.

There's just something about the Thunderbolt cable connection that can create problems, so I'm not disappointed to see the connector itself go away on future Mac designs.

I wouldn't be surprised to see USB disappear from future Mac designs altogether.

USB-C is also a lot smaller than Thunderbolt connectors are, so Apple can make thinner laptop designs even on their pro systems. The lighter, the better, as far as I'm concerned, especially when you're carrying a 15-inch Retina MacBook Pro, as I do. Even though the 15-inch rMBP is loads better than the gargantuan 17-inch MacBook Pro I used to carry, I still feel it on my shoulder when I'm carrying it in a backpack all day. Shaving any weight at all is a good thing.

So far, we've only seen USB-C on one computer — the new MacBook, which made its debut this past March. Apple has updated other Macs since then, including both Retina MacBook Pros, the MacBook Air, and the 5K iMac. But USB-C stands alone on the MacBook.

Apple still produces new Macs with fourth-generation Core (Haswell) chips, because Intel's Broadwell rollout was much slower than expected. Intel says the Skylake rollout won't have the same problems.

As it stands now, the first crop of Skylake chips won't show up until later this year. I expect it'll be a while before Apple completes the Macintosh's Skylake transition. I don't think it'll happen before the end of 2015. But we'll see what comes down the road.

Because USB-C is used for both USB 3.1 and Thunderbolt 3, I wouldn't be surprised to see USB disappear from future Mac designs altogether. Apple could instead just make Thunderbolt 3 the single external wired peripheral interface standard for the Mac going forward.

Fewer ports mean less complexity, less power usage, and less user confusion. Thunderbolt 3's compatibility with USB 3.1 means that customers who buy a Thunderbolt 3-equipped computer don't have to buy more expensive, higher performance devices. They'll be able to buy the inevitable flood of mass-market USB 3.1 products that are coming down the pike. And choice is a good thing for everyone.

Peter Cohen
  • I think this is great news. As with anything I'm sure there will be growing pains but I would love to see my next MacBook Pro sporting 4 USB-C/Thunderbolt 3 ports instead of a USB 3.0 and Thunderbolt 2 mix. I kinda hope the HDMI port stays around a bit because I don't see myself ditching my current external monitors for now but if I can get adapters I'll be happy.
  • I'm liking the idea.. No power port, no HDMI, TB 2 ports, or USB B ports.. Just 3-4 USB-C type ports. (Hoping they give us 4 USB-C (2 per left/right side) ports on 15" Pro - One used for power, 2 on each side of the laptop and I can power it from either side that I want.. ooo... glorious... :D
  • This, oh my god this. I've wanted this for so long, just thinking about makes me get excited. And if iOS devices would to USB-C can dream
  • Also, new Macbook isn't the only laptop with USB-C, Googles Chromebook Pixel now sports two USB-C ports :) Posted via the iMore App for Android
  • As well as the Asus Transformer Book T100HA Posted via the iMore App for Android
  • The MacBook's the only laptop (so far) that Mac users care about... ;) </trolling>
  • Touché!
  • hehe, actually.. thats very true.. for me.. though many have mixed environments.. My hope is that this also brings Thunderbolt 3 to the non-mac laptops as well.. I would not be surprised if Intel pushes this to OEMS.. would be nice to see TB spread.. PCI-e on a cable is soo cool... Being able to upgrade the video on a laptop with an external bay with cooling is very appealing to me.
  • Are you sure about that? "Upgrading the video on a laptop with an external bay"? most GPU cards use PCIe3x16, which is MUUUCH faster than Thunderbolt 3, which is closer to PCIe3x4 from a bandwidth perspective. I had hoped for this as well, but according to wikipedia, this is very unlikely. Have you seen an example of this external device in the works? PCIe3x16 = 126.032 Gbit/s
    PCI Express - wiki TB3 = 40Gbit/s
    Thunderbolt - wiki
  • Future is looking good, although I foresee lots and lots of dongles/adapters..
  • Honestly, I welcome the new interfaces, but it is just a slap in the face for consumers when they remove the most commonly used ports. Not everyone wants to use wireless keyboards or mice. Even my compact mirrorless camera has the ability to send the photos to my pc over wi-fi, but I choose to use USB or the SD cards reader bc they are much faster and more reliable, and have less limitations. Same for ethernet. They are going to remove connectors from the already overly priced computers, but charge the same (or more- looking at you MacBook) as the models before them, then I have to have to buy hundreds of dollars more on adapters or docks? No thanks.
  • A few things: 1. TB3 is not interlinked with Skylake. Intel has explicitly confirmed that current or previous gen (Haswell, Broadwell) can be paired with its Alpine Ridge controller that provides both the USB 3.1 and TB3 standards. This means Apple can combine this with any Mac they want without waiting for Skylake. Skylake is not required.
    2. TB3 is still reliant on DP 1.2 signaling protocol, so what Intel did was combine 2 DP1.2 channels into one channel that allows for 5K resolution at 60HZ but that monitor must support sending two DP1.2 channels into one USB-C cable. It's not a big deal but it's nice to be clear about this.
    3. Macbook's USB-C only support USB 3.1 Gen1 speed, 5Gbps. Too many folks confusing this as 10Gbps.
    4. Thunderbolt 3 is now a Display-Alt signaling protocol for the USB-C interface standard. You're intermixing things again. USB-C will be the single external wired peripheral interface for Mac from now on, not TB. TB3 is now a signaling protocol that uses USB-C's Alt Mode.
  • This looks great! When USB-C first came out on the new MacBook, despite many comments on internet, I didn't think Thunderbolt would go away, but, this totally makes sense, is a perfect implementation! Now if we could just get UHD standards to switch to DisplayPort through USB-C, as HDMI 2.0 is not enough for 4K vid with HDR & wider color gamut, we might finally have a decent universal connector for all things digital! (USB-C already includes DisplayPort as part of it's spec, without the need for thunderbolt capable computer.)
  • I wonder if Apple knew about this. It makes Apples release of the 15" look even worse than before. If the Macbook Pro machines could be updated again at the end of this year then the present machine will only sell to those who really, really must get a Pro machine. I was thinking of getting one but now I think I'll hang-on to what I have, and wait for Skylake and USB-C.
  • This is awesome, this is the first I heard about Thunderbolt 3.0 using the same port as USB Type-C. I hope the Surface lineup, and other Windows manufactures for that matter, widely adopt Thunderbolt 3.0 on their high-end machines. It'd be great, as your nice fancy pro-machine can connect to all the Thunderbolt devices AND all the USB Type-C devices, diversity and options are great! Especially since a flood of USB Type-C devices is inevitable. The way I see it: Thunderbolt 3.0 for high end, professional quality laptops, desktops and tablets w/docking stations that all need the supped-up power, then USB Type-C for more mass-market laptops, desktops, and nearly all tablets and phones (And smartwatches, perhaps?). This is very appealing to me. I just hope this time, Apple isn't the only one to adopt Thunderbolt in any meaningful way, because the potential here is huge. C'mon, industry, let's make this happen!