Cerebras CEO Says OpenAI Wanted a Much Bigger Deployment, but the Company Lacked the Data Centers, as the Stock Sinks Near Record Lows

Cerebras (CBRS) CEO Andrew Feldman said this week that OpenAI wanted to greatly expand its use of Cerebras after the first deployment performed better than expected, but that Cerebras did not have the data centers to deliver the extra capacity. The comments, made at TechCrunch Disrupt on October 13, come as investors try to work out what a reported shift by OpenAI toward Nvidia GPUs means for the newly public chipmaker. The stock was trading near record lows on Thursday.

What Feldman said

According to reports from Digitimes and BigGo Finance, Feldman said OpenAI wanted to expand supply for its next-generation model because the existing service had worked so well, and that Cerebras "did not have the data centers to handle that capacity." Because Cerebras builds its own data centers and installs its own chips, he said, securing facilities was the hurdle, not the silicon. We have not seen a full transcript, so the wording above is as reported.

The service in question launched in August: Cerebras powers an "Ultrafast" tier of OpenAI's API for GPT-5.6 Sol that runs at up to 750 output tokens per second, which OpenAI described as up to 14 times faster than standard service. Some summaries of the remarks cite roughly 800 tokens per second; the published figure is 750.

The Nvidia question

The comments land after a report on September 30 from SemiAnalysis that the Ultrafast tier of OpenAI's newer GPT-6.1 Sol model runs on Nvidia GPUs rather than Cerebras hardware, at a low batch size. Neither OpenAI nor Cerebras has confirmed which chips serve that tier. The 6.1 Sol Ultrafast tier is priced at six times the standard rate and runs at roughly 300 tokens per second, well below the 750 Cerebras delivered on the earlier model, according to OfficeChai.

The stock fell nearly 20% that week. OpenAI CEO Sam Altman then wrote on X on October 2 that "Cerebras is a close partner, and we have a deep engagement pushing on the frontiers of speed," without saying which chips run the new tier, and shares rose about 9% on October 5. Feldman's explanation, that capacity rather than performance drove the decision, fits that account but does not confirm the hardware question either way.

The business behind the story

Cerebras said in August that its manufacturing capacity would grow more than tenfold in 2026, with new lines at Flex, Sanmina and Rocket EMS. The data-center gap Feldman described is the part of that build-out that still has to be filled. OpenAI is a significant customer, and the company has also lent Cerebras $1 billion and holds warrants for up to 33.4 million shares, according to Benzinga.

The stock

CBRS traded at $137.21, down 3.0%, at 10:25 a.m. ET on Thursday, according to StockAnalysis.com, after closing Wednesday at $141.48. That is about 26% below the $185 IPO price from May and far below the roughly $350 level where it opened. Its market value is about $32.6 billion, versus close to $95 billion after its first day of trading. Monday's $146.62 close was a record low at the time, according to Benzinga, and Wednesday's close was lower still.

Supply is another pressure. Up to 19.4 million more shares became eligible for sale on Wednesday under a staggered lock-up that releases shares every two weeks through the end of October. Feldman and CTO Sean Lie sold more than $240 million of stock between August 20 and September 25 under pre-arranged trading plans. Chip stocks as a group have been weak, as covered in our midday chip recap, and Broadcom's CEO has said capital, not chips, may be AI's biggest bottleneck.