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At the same time, a new system was introduced to the Apple Store, called the Mac Pro Server. The server comes with an OS X Server unlimited license and is powered by an Intel 2.8GHz Quad-Core processor with 8GB of DDR3 memory. While the Mac Pro Server is on the lower end of the Mac Pro spectrum, it comes with substantially more horsepower than the Mac Mini Server.
Nevertheless, given its form factor, it's likely that the Mac Mini Server will become the primary focus of Apple's server strategy. Since the Mac Pro Server is boxed in a tower, it's not conducive to the rack mounts found in many server environments.