In May of 2017 Intel announced that the Thunderbolt 3 specification would be transitioning to a Royalty-Free licensing model alongside its integration into next-generation CPUs. After over 20 months it has been revealed that the technology - once very much proprietary and exclusive to Intel platforms - would be making its way into a wider selection of devices via integration into USB 4.

While a comprehensive release of USB 4's specification isn't due until the middle of the year, and actual implementation of certified products is unlikely before next year, the announcement should prove to be a boost to the Thunderbolt 3 device ecosystem. Outside of professional spheres Thunderbolt has been a niche technology that has yet to realise its promise.

PCI-Express and Displayport signalling over a single compact connector, offering up to 40Gbps bandwidth, has theoretical applications well beyond high-speed external storage. Similar techniques have been undertaken with the VirtualLink connector for virtual reality HMDs, while external graphics enclosures have shown tantalising glimpses of potential futures. For one reason or another however it has failed to take off.



Mainstream adoption of Thunderbolt 3 at a silicon level in CPUs will begin with the release of Intel's 10nm "Ice Lake" range, scheduled for widespread consumer availability later this year. This puts Intel considerably ahead of the game, especially if USB 4 certification can be grandfathered in.

Publication of a specification later this year will mean that AMD 'Zen 2' CPUs are unlikely to support either Thunderbolt 3 or USB 4 natively, but it may be possible through 3rd party controllers. Nonetheless cost and power requirements have thus-far kept it out of mainstream motherboard chipsets. In 2018 Level1Techs showed compatibility was possible on AMD's Threadripper platform by using the GIGABYTE GC-TITAN-RIDGE add-in card, and a smoother and more comprehensive implementation is by no means out of the question in the near term.

For Intel's part, they'll be contributing their expertise in the field of testing, certification and device driver support for the Thunderbolt protocol on Windows 10 and Linux which may be grandfathered into USB 4. They will also be working with industry partners to develop innovative uses for the technology beyond what's currently in play.

One thing is certain with this news, and that is that the USB Type-C is here to stay and Type-A's days may well be numbered. The latter connector will not support USB 4/Thunderbolt, while USB 4's use of the Type-C connector will remain backwards compatible with USB 2/3/3.1/3.2 & Thunderbolt 3 signalling.

SOURCE: Intel Newsroom