they used crippled export variant h800, with severed limited nvlink bandwidth, hence why they innovated and focused on compute efficiency. the very policy that is supposed to cripple china's ai progress forced them to innovate out of necessity. the bad news is that they didn't need cuda and got around a lot of the limitations through direct to the metal programming. they can port the model to huawei or amd hardware with minimal performance loss. the big news here is that nvidia's cuda moat is just as fragile as openai's moat.
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