The USB4 technical specification has been published by the USB Implementers Forum. It uses the same USB-C cables with transfer speeds up to 40Gbps, double the performance of the current USB 3.2 standard.
What is USB4?
It’s a new version of the data and power Universal Serial Bus transfer protocol and physical connectivity standard that started its life in 1996 and was popularized by the Apple iMac in 1998.
What’s the difference between USB4 and USB-C?
The new USB flavor basically merges Thunderbolt and USB-C, but it is much faster.
How fast is USB4?
USB4 offers double the performance of USB 3.2 at a maximum of 40 Gbps. However, there will three speeds offered at different tiers: 10 Gbps, 20 Gbps and 40 Gbps.
Will I be able to connect USB4 devices to my current computer?
Yes, but they will transfer data at whatever speed your existing USB ports allow.
Is the physical connector different?
It’s the same as USB-C. You will be able to connect most USB devices as it is backwards compatible with USB 3.2, USB 2.0, and Thunderbolt 3. One thing: the standard will banish USB-A (the square connectors you can't ever get in on the first try) and micro versions of USB.
Can I drive a monitor with USB4?
Yes, just like Apple computers use Thunderbolt to drive displays. The standard supports simultaneous transfer of multiple video and data streams.
As reported by sister site Tom's Hardware, a key part of the USB 4 spec is the ability to dynamically adjust the amount of resources that are available when you are sending both video and data over the same connection.
Can I connect a Thunderbolt device to USB4?
Yes, but only if the manufacturer of your PC has implemented the Thunderbolt layer of USB4. Thunderbolt support is optional in USB4 so you will have to check before buying a new computer.
Can I use it to USB4 to charge my phone or console or whatever?
Yes, and it will be fast. The new USB4 standard includes USB Power Delivery, a protocol that will allow to safely charge anything at the fastest rate available for that device.
When are we going to see the first products with USB4?
It is expected that they will start arriving sometime in 2020, probably in the second half of the year.
So what does USB4 mean for consumers?
Aside from the speedier data exchange and faster charging, the widespread adoption of USB4 will mean cheaper, faster devices and adapters for everyone thanks to economies of scale.