AWS Stargate-smashing Rainier megacluster goes live • The Register
Never mind Sam Altman’s Stargate, which is just beginning to open its portal to distant AI-fueled worlds: Amazon’s competing mountain of AI compute power is already up and running.
Amazon Web Services today announced that Project Rainier, its Stargate-rivaling AI “UltraCluster”, is now up and running, with “nearly half a million” Trainium2 chips serving the massive machine across multiple datacenters. Just how many datacenters and how much compute power Rainier actually offers wasn’t shared, but AWS assured the public in its press release that the machine is “one of the world’s largest AI compute clusters,” and it came online in record time.
“Project Rainier … is now fully operational, less than one year after it was first announced,” AWS said – and it’s not stopping at that half-a-million Trainium2 chips, either. The cluster is already being used by Amazon’s AI partners at Anthropic, who the company said will be scaling “to be on more than 1 million Trainium2 chips – for workloads including training and inference – by the end of the year.”
From what we know based on earlier discussions with AWS staff in our preview of Project Rainier from the summer, each one of the datacenters housing the project will be massive. An AWS spokesperson told us in July that one site in Indiana that is now partially online as part of the Rainier cluster will eventually span 30 datacenter buildings, each measuring 200,000 square feet.
We reached out to AWS for more information on the Rainier cluster, how many datacenters currently encompass it, and how large it’ll be by year’s end, but didn’t hear back.
AWS is locked into the AI capacity battle versus the Stargate joint-venture project between OpenAI and partners like Oracle and SoftBank. There were around 200 megawatts of Stargate compute power online at the OpenAI-backed initiative’s Abilene, Texas, datacenter as of earlier this month, and commitments from OpenAI’s partners plan to expand the Texas Stargate DC to 1.2 GW of capacity by mid-2026. Oracle is supposed to help add 5.7 GW of capacity in the next four years.
Amazon’s logistical expertise certainly helped it build fast, but it’s also got a hardware advantage.
“Unlike most other cloud providers, AWS builds its own hardware, and in doing so, can control every aspect of the technology stack, from a chip’s tiniest components, to the software that runs on it, to the complete design of the datacenter itself,” AWS said in a press release.
Now if only the cloud giant can iron out those reliability kinks that’ve been popping up recently, everything’ll be peachy. ®


