USB-C can reach 120Gbps with newly released USB4 specification version 2.0

We’ve said it before and we’ll say it again: USB-C is confusing. The USB-C port or cable may support different speeds, wattages, and other features depending on the specification used. Today, USB-C can support a variety of transfer rates, from 0.48 Gb/s (USB 2.0) to 40 Gb/s (USB4, Thunderbolt 3, and Thunderbolt 4). The situation is only getting worse as today the USB Developers Forum (USB-IF) published the USB4 specification version 2.0. It adds additional support for 80 Gb/s bidirectional bandwidth, as well as the additional ability to send or receive data at up to 120 Gb/s.

USB-IF first let us know about USB4 version 2.0 in September, saying it will support data transfer rates up to 80Gbps in either direction (40Gbps per lane, four lanes in total) thanks to a new Physical Layer (PHY) architecture. based on PAM-3 signal coding. For what it’s worth, Intel also showed Thunderbolt at 80Gbps, but hasn’t released an official spec yet.

USB4 2.0 offers a nice, potential step up from the original USB4 specification, which introduced additional support for 40Gb/s operation. You just need to be sure to check the specs to see what kind of performance you are getting.

With the release of USB4 version 2.0 products, you will be able to achieve 80Gb/s speeds with passive USB-C cables, which are currently running at 40Gb/s, but you will have to buy a new cable if you want longer active 80Gb/s. With.

120Gbps is optional

USB-IF today confirmed that USB4 version 2.0 will go even further, optionally supporting data transfer rates up to 120Gbps over three lanes.

“Optional for certain applications such as driving USB4-based high-performance displays, the USB Type-C signal interface can be configured asymmetrically to carry up to 120Gbps in one direction while maintaining 40Gbps in the other direction,”it says in the IF message.

Typically, a USB4 version 2.0 port that supports 120 Gb/s operation will transmit and receive data at 80 Gb/s. When a product is connected to a port, “a USB4 discovery process controlled by the system software determines whether the 120Gb/s configuration is the preferred mode of operation. – Chairman of the Board and CEO of IF, Ars Technica said.

The new specification supports both transmitting and receiving data at 120 Gbps; however, Saunders said it is “most likely”that the application will see data being transferred from the computer to the high-end monitor at 120Gbps, leaving 40Gbps of bandwidth to send data to the system.

The new USB-C specification is designed for devices with extreme display requirements, including resolutions above 4K, gamer-level refresh rates, HDR color, and multiple monitors. Bandwidth requirements from content creators and gamers continue to exceed the original 40Gbps limit.

We could also see external SSDs and external GPUs also using the USB4 version 2.0 protocol. But both remain more niche products, even among today’s USB4 and Thunderbolt options.

The new USB4 specification version 2.0 also includes support for USB 3.2 tunneling at 20Gbps, up from the previous 10Gbps. And the new protocol supports the DisplayPort 2.1 specification announced today by VESA, as well as PCIe 4.0.

With the USB4 specification version 2.0 released today, we don’t expect supporting products for “at least 12 to 18 months,”according to CNET ‘s USB-IF statement.

However, when these products come out, USB-IF hopes they won’t be presented to consumers as “USB4 Version 2.0″or even some type of “SuperSpeed ​​USB”. After 12 years, USB-IF no longer recommends vendors use terms like “SuperSpeed ​​USB 20Gbps”(for example, for the USB 3.2 Gen 2×2 specification), but instead chooses terms like “USB 20Gbps”.

If USB-IF had its way, products using its new open standard would be called “USB 80Gb/s”. Ultimately, however, USB-IF has no control over this, and you will find that many vendors do not list USB speeds, and some use specification names such as USB4 Version 2.0. Recommended USB-IF logos focus on speed and power.

Today, USB-IF also updated the USB Type-C and USB Power Delivery cable and connector specifications to support USB4 version 2.0.

Naming complaints and potential confusion aside, the new USB4 version 2.0 standard offers technology to adapt to our changing needs as products become more bandwidth hungry and USB-C becomes more common and, in some places, mandatory. connector.