The restrictions are based on performance thresholds per commerce control list category 3. Specifically 3A090 which controls the export of ICs that have memory bandwidth exceeding 600Gbyte/s and processing exceeding 4800Tops (600T iops 8bit, 300T flops 16bit)
It's the combination of tensor cores (660T iops for 4090) and ram bandwidth which are only just tripping it into the export restriction, which is why lower tier cards and AMD aren't currently affected.
Not sure how this will affect things in the long term, it may well impact the ability of Nvidia to release consumer cards which are much faster than 4090.
It's the combination of tensor cores (660T iops for 4090) and ram bandwidth which are only just tripping it into the export restriction, which is why lower tier cards and AMD aren't currently affected.
Not sure how this will affect things in the long term, it may well impact the ability of Nvidia to release consumer cards which are much faster than 4090.