We had 8 systems in the Top 500 list at Weta Digital back in 2008 which were liquid cooled HP servers for rendering Avatar. We used one of the techniques mentio

We had 8 systems in the Top 500 list at Weta Digital back in 2008 which were liquid cooled HP servers for rendering Avatar. We used one of the techniques mentioned in the article: liquid to liquid heat exchangers. Each rack was fully sealed with its own heat exchanger which pumped in cool water and sent off warm water to chillers on the roof. Actually the warm water condensing would attract seagulls in the winter which was a problem since we were right next to the airport. The datacentre was designed by an engineering firm which usually built dairy factories. Every once in a while something would go wrong with the cold water delivery system and the servers would overheat and shut down in about 30 seconds.