But they are also prohibited from being supplied to China as part of the sanctions.
It turns out that Chinese craftsmen are making “Frankenstein monsters” not only from the GeForce RTX 4090. The RTX 3090 and RTX 3090 Ti models are also reportedly being turned into accelerators for AI. They are not as powerful as Nvidia's current flagship, but they have the same 24 GB of memory. True, like the RTX 4090, supplies of the RTX 3090 to China are also prohibited.
Tom's Hardware doesn't say whether the RTX 3090 is undergoing as complete a redesign as the RTX 4090, but the cooling systems are definitely being changed to “turbines” since the latter take up less space and are better suited for conditions where multiple accelerators are installed in the system.
It is possible that over time the Chinese will take up less powerful video cards. For example, the RTX 4080 or the upcoming RTX 4080 Super.