A modular computing system for a data center includes one or more data center modules including rack-mounted computer systems. An electrical module is coupled to the data center modules and provides electrical power to computer systems in the data center modules. One or more air handling modules are coupled to the data center modules. The data center module may include two pre-fabricated portions, each portion including a row of racks of computer systems. The two computing module portions of the data center module may combine to form a computing space when coupled to one another.