Cerebras Systems Inc. CEO Andrew Feldman said SpaceXAI, formerly xAI, moved into rented AI computing because its Grok model struggled with early enterprise market adoption, leaving billions of dollars in hardware idle. On the Sourcery podcast on Monday, Feldman explained that SpaceXAI could not afford to leave equipment idle, stating, "They had these GPUs sitting around, and that’s a bad idea." He pointed to IPO-bound Anthropic’s agreement to use SpaceX’s Colossus 1 data center in Memphis, Tennessee, which provides more than 300 megawatts through over 220,000 Nvidia GPUs. In May, Anthropic agreed to pay $1.25 billion per month for Colossus and Colossus II capacity through May 2029, with both sides able to terminate with 90 days’ notice. Feldman said of the lease, "We had all these GPUs. Our model wasn’t a success, but we can have a great business by stepping into what is a constrained market." SpaceXAI launched Grok 4.5 on July 8, calling it its strongest model for coding, agentic tasks and knowledge work. Musk recently called Anthropic "obviously currently the leader in AI."