Intel has introduced Thunderbolt 4. The data rate remains at 40 Gb/s, as already with Thunderbolt 3. So nothing has changed in terms of speed. However, an improvement is taking place in other places.
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So now cables can be used which are up to 2m long. And it is specified that there can be hubs that have up to four connectors for Thunderbolt 4 devices. Conveniently, a computer attached to a hub can now wake up at the touch of a button. So the signal from the connected keyboard is correctly used via the hub to wake up the computer.
Intel has also specified that a computer that offers a Thunderbolt 4 port must be able to drive at least two 4K monitors. With Thunderbolt 3 it is only one. Nice for further compatibility (and still somewhere between annoying and funny): Thunderbolt 4 is compatible with Thunderbolt 3 and USB4. Also with regard to the USB-C plugs and sockets used. So always pay attention which standard the cable you’re using supports, otherwise you’ll have a long troubleshooting to do (suggestion: mark the cables with 1, 2 or 3).