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> with a vanishingly small fraction of flops and a small fraction of memory bandwidth

Is it though?

Wikipedia says [1] an M3 Max can do 14 TFLOPS of FP32, so an M3 Ultra ought to do 28 TFLOPS. nVidia claims [2] a Blackwell GPU does 80 TFLOPs of FP32. So M3 Ultra is 1/3 the speed of a Blackwell.

Calling that "a vanishingly small fraction" seems like a bit of an exaggeration.

I mean, by that metric, a single Blackwell GPU only has "a vanishingly small fraction" of the memory of an M3 Ultra. And the M3 Ultra is only burning "a vanishingly small fraction" of a Blackwell's electrical power.

nVidia likes throwing around numbers like "20 petaFLOPs" for FP4, but that's not real floating point... it's just 1990's-vintage uLaw/aLaw integer math.

[1] https://en.wikipedia.org/wiki/Apple_silicon#Comparison_of_M-...

[2] https://resources.nvidia.com/en-us-blackwell-architecture/da...

Edit: Further, most (all?) of the TFLOPs numbers you see on nVidia datasheets for "Tensor FLOPs" have a little asterisk next to them saying they are "effective" TFLOPs using the sparsity feature, where half the elements of the matrix multiplication are zeroed.



TFLOPS are teraflops not “tensor flops”.

Blackwell and modern AI chips are built for fp16. B100 has 1750 tflops of fp16. M3 ultra has ~80tflops of fp16 or about 4% that of b100




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