Originally Posted by Gordon Scott
I don't have Thunderbolt, so I'm not directly affected, but if this video it true (I did do a little sanity checking), then it appears important to be aware of this. Intel have dropped backwards compatibility of T4 to T2 and T1.

According to Intel, this is not true and TB4 is backward compatible. According to many who've tested this, it most certainly is. It affects PCs but not Apple.
Thunderbolt 4 discussion on Gearspace

Originally Posted by mrgeeze
As I read AAPL stopped shipping Intel Macs in 2020. Expect more and more things to not work with them.

You couldn't be more wrong. Apple's implementation of TB3 (Intel) and TB4 (Apple Silicon) is backward compatible to TB1/2 all the way USB 2/1.1. Not only does Apple say this but I have tested it and know it to be true.

TB3/4 are based on the USB4 spec. Intel certifies and licenses Thunderbolt but rarely supplies the hardware. Apple branded TB4 cables have no problem with this and all USB4 cables that I have tested, likewise.

Unfortunately, USB-C is a port, not a protocol, and is a major hot mess. One must read the specs of a cable carefully to know what is and isn't supported.


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