USB-IF Sheds Light on Intel’s Thunderbolt 4 standard – It’s not a big leap over Thunderbolt 3

Intel promises Thunderbolt 4 with Tiger Lake

USB-IF Sheds Light on Intel’s Thunderbolt 4 standard – It’s full-fat USB4

Thunderbolt 4 was one of Intel’s surprise reveals of CES 2020, but according to the hardware gurus over at the USB Implementors Forums (USB-IF), Thunderbolt 4 won’t offer generational leap that users have come to expect. 

At, USB-IF representatives have reportedly discussed Intel’s Thunderbolt standard in detail at CES 2020, confirming that Thunderbolt 4 is intel’s brand name for a fully-featured USB4 implementation.  Given USB4’s use of Intel’s Thunderbolt 3 specification, it is easy to see why Intel didn’t reveal the data rates offered by the standard, aside from cryptic “4x the throughput of USB 3″ comment. 

With this information, we can now reveal Thunderbolt 4 as a mere reworking of Thunderbolt 3, offering the same maximum data rates of 40Gbps. Intel’s Tiger Lake series processors will release with support for Thunderbolt 4, making Intel the first company to release fully-featured USB4 products. This was always expected, given Intel’s creation of Thunderbolt 3, the standard which acts as USB4’s technological base. 

Thunderbolt 4 does not offer a generational performance leap over Thunderbolt 3, making the standard disappointing for those who wanted Intel to push its Thunderbolt standard further. Thunderbolt 4 is a sidestep, rather than a step forward. 

Even so, Thunderbolt 4 promises full USB4 support, which is a meaningful distinction given USB4’s optional functions. With USB4, half-speed 20Gbps links are available, and PCIe tunnelling is an optional feature. Thunderbolt 4 promises that all of USB4’s optional features are active, which is something that not all USB4 devices will offer. Some USB4 ports/devices will provide a maximum of 20Gbps speeds, whereas Thunderbolt 4 ports/devices are guaranteed to deliver full-fat 40Gbps link speeds. 

What about USB 3.2×2? 

USB 3.2×2 is a standard which offers users 20gbps link speeds, which are the same speeds offered by USB4’s minimum permitted data rates. This means that USB 3.2×2 is likely to be dropped from most future devices in favour of USB4, as it offers users the same speeds and the potential to support optional features like PCIe tunnelling and higher 40Gbps data rates. 

Hopefully, this move will also kill off some of USB’s terrible marketing decisions moving forward, like USB 3.0’s rebranding to USB 3.1 Gen1 and later USB 3.2 Gen 1. Now, USB should focus on USB4, and work to deliver its users a clear and understandable ecosystem. Seriously, who thought that USB 3.2×2 Gen 2 was a good name for a new product?  

So far, Intel has not commented on the performance of its new Thunderbolt 4 technology, but its silence on the technology at CES is telling. Thunderbolt 4 is full-fat USB4, which means that it is, for the most part, Thunderbolt 3. 

You can join the discussion on Intel’s Thunderbolt 4 technology on the OC3D Forums.