

I made a math mistake. Theoretical minimum cost to openAI is $3.15/m ($3.30/m with electricity) tokens, as cerebras has fixed context windows per user, and codex spark allows 3.33 concurrent users per node. That is still $16.50/m optimistic (20% of theoretical capacity) cost for $14/m revenue.
I guess there is a market for very fast response tasks. OpenAI does have a routing system that charges a high cost per token, but gets most of the work done by their smaller/cheaper models behind the scenes.
But, this turns out not to be ultra stupid if OpenAI has the internal training/improvement token workload to completely saturate the datacenter for its own use. Cerebras does have a training advantage over nvidia. It’s immature software stack only applies to cutting edge inference techniques.








It’s a $20B deal. Covering just first 3 years of full datacenter lease. It’s a bit strange of a deal where 3 year lease payments are higher than cost of datacenter, and an Nvidia alternative would have better economics, even if Cerebras can do some things well. Altman with a personal stake, can explain OpenAI’s generosity in the deal.