The current AMD Ryzen 5000 series processors do not yet have support for external graphics cards through the Thunderbolt 3 and USB 4 ports. It seems that AMD plans to include support for USB 4 with support for connecting an external GPU in its next Ryzen 6000 series processors.
Reference to this compatibility feature has been found in drivers released by AMD engineers. A new Linux kernel driver patch has been shipped for Penguin OS, including USB 4 DisplayPort 1.4 tunneling, a necessary feature of USB 4. Since the patch is intended for Yellow Carp, it is likely intended for users. AMD Ryzen 6000 processors, codename used for AMD Ryzen 6000 Rembrandt processor on Linux.
External GPUs will be able to use USB 4 and work on AMD
Today, eGPUs are connected through the Thunderbolt 3 port, a technology that is currently only available on Intel-based systems. AMD CPUs support USB 3.1, but that doesn't work with most external graphics cards. There are unofficial methods to make a connection via USB, but the bandwidth and latency provided are not enough.
Thunderbolt 3 is no longer exclusive to Intel, and USB 4 includes support for TB3, opening up to a much more audience. AMD processors do not yet support USB 4, so Ryzen users have not yet had a way to use an external GPU. But it looks like things may change soon for AMD users if the new leak proves to be true.
External graphics cards are a way to offer graphics power in a laptop and not sacrifice its base portability, so if this leak is confirmed, many laptops with AMD CPUs and with USB 4 will be able to improve their graphics capacity thanks to an external graphics card. . The next generation of AMD processors, Zen 4, is confirmed for release in 2022. Although no official date has been revealed, speculation points to AMD dropping the new CPUs early in the year.
