We have received reports of performance issues with the AMD Ryzen Threadripper 3970X and 3990X processors, featuring 32/64 cores (64/128 threads). The system behaves as if Cubase/Nuendo is processing on a single core only, and the performance is far from what could be expected under normal conditions.
Tests with 1st generation AMD Ryzen Threadripper using 16 cores do not show this behavior.
Both processor models use a different architecture and are basically entirely different CPUs compared to the older models. We could verify the incompatibility a few days ago using a customer's system trace.
Use Cubase 12 and other upcoming product releases (Nuendo 12 etc.) for support (see above).