assuming 1) memory bandwidth is the bottleneck and 2) you can keep the tensor values in cache or registers.
I think that GPUs are still vector processing engines, so they should scale with 4x... But assuming google architected the TPU correctly, it should be 16x as fast (I think the architecture is actually that of a rank-2 tensor).
I think that GPUs are still vector processing engines, so they should scale with 4x... But assuming google architected the TPU correctly, it should be 16x as fast (I think the architecture is actually that of a rank-2 tensor).