Rack-mount server-simulating load banks discharge heat while consuming power to accurately mimic the load of a server processing a workload. Data centers test cooling and power supply operation with load banks rather than software simulations for more real-world accuracy, such as air-flow blockage in the rack caused by the server-sized load bank, or dust in the air from improper filtration. Avtron, ComRent and Mosebach are server simulator load bank manufacturers. http://www.cnloadbank.com/