Thunderbolt 3 - 40 Gbps Thunderbolt, USB 3.1, DP 1.2 all on USB-C

A substantial upgrade for Thunderbolt

Today at Computex, Intel took the wraps off of the latest iteration of Thunderbolt, a technology that I am guessing many of you thought was dead in the water. It turns out that's not the case, and this new set of features that Thunderbolt 3 offers may in fact push it over the crest and give it the momentum needed to become a useable and widespread standard.

First, Thunderbolt 3 starts with a new piece of silicon, code named Alpine Ridge. Not only does Alpine Ridge increase the available Thunderbolt bandwidth to 40 Gbps but it also adds a native USB 3.1 host controller on the chip itself. And, as mobile users will be glad to see, Intel is going to start utilizing the new USB Type-C (USB-C) connector as the standard port rather than mini DisplayPort.

View Full Size

This new connector type, that was already a favorite among PC Perspective staff because of its size and its reversibility, will now be the way connectivity and speed increases this generation with Thunderbolt. This slide does a good job of summarizing the key take away from the TB3 announcement: 40 Gbps, support for two 4K 60 Hz displays, 100 watt (bi-directional) charging capability, 15 watt device power and support for four protocols including Thunderbolt, DisplayPort, USB and PCI Express.

View Full Size

Protocol support is important and Thunderbolt 3 over USB-C will be able to connect directly to a DisplayPort monitor, to an external USB 3.1 storage drive, an old thumb drive or a new Thunderbolt 3 docking station. This is truly unrivaled flexibility from a single connector. The USB 3.1 controller is backward compatible as well: feel free to connect any USB device to it that you can adapt to the Type-C connection.

View Full Size

From a raw performance perspective Thunderbolt 3 offers a total of 40 Gbps of bi-directional bandwidth, twice that of Thunderbolt 2 and 4x what we get with USB 3.1. That offers users the ability to combine many different devices, multiple displays and network connections and have plenty of headroom.

View Full Size

With Thunderbolt 3 you get twice as much raw video bandwidth, two DP 1.2 streams, allowing you to run not just a single 4K display at 60 Hz but two of them, all over a single TB3 cable. If you want to connect a 5K display though, you will be limited to just one of them.

View Full Size

For mobile users, which I think is the area where Thunderbolt 3 will be the most effective, the addition of USB 3.1 allows for charging capability up to 100 watts. This is in addition to the 15 watts of power that Thunderbolt provides to devices directly - think external storage, small hubs/docks, etc.

Continue reading our preview of the new Thunderbolt 3 technology!!

View Full Size

That protocol capability will extend to the other devices as well in the Thunderbolt chain as long as they are integrating Intel's Alpine Ridge controller. This means if you buy a monitor with a USB-C Thunderbolt 3 pass through connection then you will have the ability to connect a USB device, a DisplayPort device or another Thunderbolt device to it. Connecting a USB 3.1 SSD to a monitor would actually utilize the monitor as the host device, passing the data back to the PCs via PCIe.

One interesting note about the physical connectivity: the USB 3.1 and the Thunderbolt connections will utilize the same physical wires. This means that a TB3 port will only be able to run as either a Thunderbolt 3 or a USB 3.1 connection, not both. That is why a USB 3.1 device must be installed after the last daisy chained Thunderbolt device. USB 2.0 has its own dedicated wires in the cable though so you can run USB 2.0 devices off of a Thunderbolt device but still pass Thunderbolt on to the next product in the chain.

(Note: an exception to this scenario above is if a TB3 device implemented a separate USB 3.1 controller itself and thus could offer that capability passed through PCIe directly.)

View Full Size

Possibly the most important utilization of Thunderbolt 3 will be in single-cable docking stations. With one connection from your notebook to a dock you can add Gigabit Ethernet, multiple 4K display connections, keyboards, mic, external storage and more. This single connection from your dock to the notebook will not only pass the data back and forth but will also allow up to 100 watts of power for charging said notebook. This would basically mean a powered docking station on your desk would need a single cable for power and all accessory connections.

View Full Size

You might think that 40 Gbps is overkill for the device connectivity you use, and you may be right. But the example on the right in the slide above shows a user with two 4K displays, a USB 3.1 storage device, some USB 3.0 hardware and a Gigabit Ethernet connection, just coming in at the peak 40 Gbps capability of TB3. But even a user with a single 4K display and USB 3.1 storage device could exceed the bandwidth available in Thunderbolt 2, giving credence to the need for this upgrade.

View Full Size

Oh here we go again: the holy grail for enthusiasts. External graphics. Intel is promoting the idea and helping with validation this time so I have a lot more confidence that it will work, mentioning specifically that it is working with AMD to make sure that hot plug capability is working without random blue screens of your device. (Sorry, no mention of NVIDIA support quite yet.) Look, this is something we have all wanted for a long time - the ability to have a thin and light notebook that we dock and play games on without having to settle for sub-par graphics performance or requiring two machines. TB3 offers more bandwidth, more flexibility and has Intel's backing in support for external graphics; I'm much more hopeful than I have been before.

View Full Size

One thing we saw announced last year that never really picked up steam was Thunderbolt networking. The idea of "free" peer to peer networking at 10 GigE speeds with multi-OS support for large data transfers and small workgroups is compelling.

View Full Size

In terms of cabling, there are a few different options. First, the passive cable speed limit will be 20 Gbps and will be the lowest cost option you can get. It will still support USB 3.1 and DisplayPort 1.2 in addition to Thunderbolt but it will be limited to the Thunderbolt 2 speeds. You'll have to step up to an active copper cable to get 40 Gbps but you do lose the integrated DP 1.2 support. Also, cable length will be limited to 6 ft or so, about the same length we are used to today.

Most interesting are the active 40 Gbps optical cables that are still in development and targeted for 2016. Running at lengths up to 60 meters, expect these cables to be quite a bit more expensive but to offer the full flexibility of Thunderbolt 3.

View Full Size

For backwards compatibility Intel is going to offer an adapter that can function both ways you might want it to: from TB3 host to a current TB device AND from a current TB host to a TB 3 device.  No word on pricing or availability of such an adapter but we are glad to see Intel thinking ahead of it.

My take away from our Thunderbolt 3 briefing is basically that Thunderbolt keeps getting better, even if I can't seem to convince people to really use it. Hopefully with the functionality of TB3 expanding to support USB 3.1, and thus not forcing system builders and users to selectively choose between the two standards, will broaden its adoption. Having a single connection that can now handle PCI Express, Thunderbolt devices, DisplayPort 1.2 4K displays and even USB 3.1 while providing up to 100 watts of charging power really is a best-of-all-worlds solution.

Thunderbolt 3 devices will start shipping this year though they won't ramp up until 2016 according to Intel. When asked about pricing for the Alpine Ridge controller Intel didn't offer any numbers, but if adoption is to increase at a clip that I want to see, costs had better drop from where they were over the previous two generations. A standard connection interface like this can only be great if it actually utilized by consumers.

What do you guys think? Are ready for this third iteration of Thunderbolt?

June 2, 2015 | 01:56 PM - Posted by Anonymous (not verified)

Are they *actually* going to support external GPUs this time? OEMs have wanted to for years but been rebuffed by Intel's non-desire to certify devices.

June 2, 2015 | 03:45 PM - Posted by Anonymous (not verified)

You know that the laptop OEMs are not going to whitelist the expansion boxes, or desktop GPUs, that allow just any external GPUs to be plugged into their laptop SKUs, that's not their business model, unless it is some overpriced weak GPU branded by the OEM for the OEM's specific laptop model. How many laptops have you seen that have USB type-c form factor plugs are there in some new devices that actually are using a USB 3.1 controller chip!, most are using the USB type-C plug for its electrical power delivery capability, but are only connecting the type-C plug to a USB 3.0 controller chip.

Intel is offering its thunderbolt 3, via the a hybrid USB type-c plug with the thunderbolt wires added to the plug's pinout. Users will get thunderbolt connectivity, and true USB 3.1 connectivity via a single plug. Intel can now keep the minimalists at Apple Happy with their single plug fetish, while still keeping its thunderbolt controller sales to Apple, all while providing more thunderbolt bandwidth for the professional users that may have begun to move away from Apple, dew to Apple's pathological design mavens. the Mac Pro users will get 6 of these thunderbolt 3 ports on the Mac Pro's refresh, and get a little more external bandwidth to attempt to replace the lost PCIe expansion lanes that Apple's pathological design minimalists took when they created the minimalist design ethos Trash Can Mac in the first place.

It's saving space in the Z dimension(Apple hates the Z dimension) going with the USB type-C's thinner form factor, even relative to the modified mini display port plug that thunderbolt adopted for its first plug and first revision(TB 2). So in a few years it will become a one size universal plug Frankensteined together from the USB type-C form factor plug and all the wires of the other standards.

Laptop OEMs are a greedy bunch, intentionally hobbling their older hardware with lack of sufficient driver updates all to keep the customers on a continuous hardware update treadmill, as for laptops any significant updating requires a new purchase of an entire device. Intel's adaption of its new thunderbolt was driven as much by its need to placate its largest customer, more than it was the need to innovate in and of itself, but still its good to see the lard A$$E$ at Intel innovating. It's even more funny when looking back at Intel's Thunderbolt development that they were using a USB type-A plug form factor during development, and Sony had a Laptop with an external thunderbolt GPU connected via a USB type-A form factor plug.

So it all comes around again, and maybe a USB Type-c from factor with appropriate pins added will suffice for all needs, and put the adaptor folks out of business once and for all, but I would not get my hopes up just yet.

June 2, 2015 | 01:57 PM - Posted by Anonymous (not verified)

Super nice! Love the external graphics option.

Now we need to see the chip in some nice Windows products.

June 2, 2015 | 02:29 PM - Posted by sotoa

It'a about time Thunderbolt did something, and boy did it ever! Sounds very exciting!

June 2, 2015 | 02:49 PM - Posted by BBMan (not verified)

Now THAT's a speed jump that gets your attention.

Onward USB 4.0!

June 3, 2015 | 04:16 PM - Posted by Edmond (not verified)

Exactly... the 17 to 25 Gbit/s that dp1.2 > 1.3 went for makes me think they like to waste our time.

I much rather see the 40 Gbit/s TB3 take over instead of displayport, hdmi or anything else that fails to deliver

June 2, 2015 | 03:35 PM - Posted by BillDStrong

Um, the 100w is a function of the USB Type C connector, and has nothing to do with USB 3.1. I mention this as the Type C connector can and has been used on USB 3.0 devices and supports the 100w. This is confusing.

I do hope this takes off, but ai think this one cable for all things could cause some confusion to consumers.

Luckily, the way to solve this is to make all connections on the computer TB 3, then we won't have to worry about it.

June 2, 2015 | 04:28 PM - Posted by Anonymous (not verified)

Most people will never get that the plug form factor and electrical power delivery standard of USB type-C plug is somewhat different than the actual USB (2.0, 3.0, and 3.1) data transmission standard that requires a separate controller chip to implement. The plug is just a place to route the connections through in a standardized way, and most of the Technical press do not even know how the standard/s works themselves, or even took the time to try to inform their readers of the standards in the first place. Ryan did a good job of explaining this when the technology was first introduced, but a lot of the other technology writers out there are mostly writing ad copy masquerading as actual reviews or explanations of the technological standards involved, so the majority of "technology" writers/press are actually marketing monkeys/hacks with no real knowledge of technology.

Hell even at AMD's latest technology tradeshow/symposium/announcement had a technical person and marketing executive being asked on camera to describe Carrizo, and the marketing executive made a fool of himself while the technical engineering head/executive was very impressive and cogent in his description of Carrizo, and HSA 1.0 standards. Marketing and non engineering folks are worlds apart, and AMD's marketing executives need to keep their traps shut when it comes to describing complex technology, and allow their engineering folks to properly describe how the technology works, and the technologies' advantages would be much clearer. The video of the interview in on youtube, the marketing/managerial executive needs to be gone, and someone with a better grasp of the technology, needs to be answering the questions, thank goodness for that engineering person/executive.

I can not in any existing language adequately describe my disgust of the marketing "profession", or the MBAs that are in control of most technology companies, but damn are AMD's marketing/managerial minions mostly interns, and AMD needs to hire a competent technology editor(with an appropriate engineering background) to overview and help AMD's marketing produce cogent primers on their new hardware and HSA technologies.

June 2, 2015 | 06:18 PM - Posted by PhoneyVirus

I think Intel finally took there pins out there sockets and got it together for once. Who wouldn't want to have a Tunderbolt 3 connection with USB Type-C connector on it. Now if there was only some kind of hardware to purchase so that you could use the new technology.


June 2, 2015 | 06:20 PM - Posted by Anonymous (not verified)

"more flexibility and has Intel's backing in support for external graphics; I'm much more hopeful than I have been before."

I assume you meant "baking".

While the external gpu stuff is an interesting idea, it is actually quite expensive. You have to have an external enclosure with a ~300 W power supply before you even get into cost of the graphics card. They would need to be a much higher volume component before the prices will come down.

June 2, 2015 | 10:26 PM - Posted by Ryan Shrout

As in cooking?

June 2, 2015 | 11:10 PM - Posted by BillDStrong

Actually, how much does a motherboard cost to make? If they sell for, say, $100, they must be able to make money off of them, right? So, how many PCI-E slots come on a mother board? So, not that expensive, right? Not in bulk, at least.

Now, how a out a power supply that doesn't need 500 plugs on it? I figure you could get the whole unit to cost less than 50 bucks, if you try real hard. Now, who are you going to sell it to, in order to get big volume? Theres the rub.

So, I figure they need to make it a multifunction device. make it a docking station that happens to include AMD or Nvidia Graphics. (Will Nvidia work with just a 4x connector with just one card? Maybe a mobile part?)

Then add some USB ports, several Display Port/HDMI/DVI ports, and other useful ports. Sell it as a business device for serious powerpoint users. And get the price down for the rest of us.

Yes, I am only half joking.

June 3, 2015 | 01:10 AM - Posted by Anonymous (not verified)

When I saw news of this... I started wondering...
What happened to DockPort?

From a simple google search I could only find news from when it was talked about and chipsets, but no actual devices or even any boards supporting it.

Not that it matters much as TB3 seems to fix all that was "wrong" with TB1 and TB3, which led to DockPort being proposed to begin with.

June 3, 2015 | 06:47 AM - Posted by Mobile_Dom

as far as i know, DockPort died when USB-C got DP alt-mode support, it didnt really have a reason to exist after that

June 3, 2015 | 01:16 AM - Posted by Hakuren

It all looks nice on paper, but let's not forget that USB is an open standard (just like DP) and Thunderbolt is proprietary crap just like FW was which is officially D.E.A.D.

As long it won't raise prices I'm in, but with patent troll like Apple behind Thunderbolt project frankly I very much doubt it.

C'mon USB 4.0, show Thunderbolt it's place in line.

June 4, 2015 | 01:41 PM - Posted by Just_My_Opinion (not verified)

Alright, more adapters! Now my collection will never be complete.

Post new comment

The content of this field is kept private and will not be shown publicly.
  • Lines and paragraphs break automatically.
  • Allowed HTML tags: <a> <em> <strong> <cite> <code> <ul> <ol> <li> <dl> <dt> <dd> <blockquote><p><br>
  • Web page addresses and e-mail addresses turn into links automatically.

More information about formatting options

By submitting this form, you accept the Mollom privacy policy.