Oracle 2020 A100 Cluster is a large GPU cluster operated by Oracle, located in the United States, in the private sector. It came online around September 2020. At that moment it ranked number 20 among known clusters.
It is built on 512 NVIDIA A100. That amounts to about 161 H100e of AI compute. The cluster draws roughly 0.45 MW. Its hardware is estimated at $14M.
Epoch AI rates the certainty of this record as likely. Slightly uncertain if they were just saying that they could build clusters up to 512 A100 in size, or if this was actually already available and built. It seems likely it was available, though