So, as a lower bound we’re talking 3-4000 GPUs and as an upper bound 3-4e9. Overall, more uncertainty than LeCun’s estimate but in very roughly the same ballpark.
This isn’t a lower bound according to Carlsmith as he says:
Overall, I think it more likely than not that 1e15 FLOP/s is enough to perform tasks as well as the human brain
Also you say:
This isn’t a lower bound according to Carlsmith as he says:
Emphasis mine.
Thanks for the correction! I’ve updated the post.