Side car prototype

A closer look at the rear-door heat exchanger put on the back of this rack of servers. The coils you can see circulate cold water that is cooled by the building's chiller. While the fans on the server next to it generated heat over 90 degrees, the back of this one was cool to the touch. Data from the temperature sensors is fed into a central console, allowing IBMers to automate both the air and water cooling systems.