Eni HPC5 is a large GPU cluster operated by Eni, located in Italy, in the private sector. It came online around February 2020. At that moment it ranked number 5 among known clusters.
It is built on 7,280 NVIDIA V100. That amounts to about 460 H100e of AI compute. The cluster draws roughly 4.03 MW. Its hardware is estimated at $140M.
Epoch AI rates the certainty of this record as confirmed.