Azure OpenAI GPT-3 Cluster is a large GPU cluster operated by Microsoft, OpenAI, located in the United States, in the private sector. It came online around April 2020. At that moment it ranked number 4 among known clusters.
It is built on 10,000 NVIDIA V100. That amounts to about 632 H100e of AI compute. The cluster draws roughly 6.55 MW. Its hardware is estimated at $192M.
Epoch AI rates the certainty of this record as likely. It has "since been upgraded to include tens of thousands of A100 chips". Rumors suggest that it is in Washington State