Apple Mac Pro "Eight Core" MB451LL/A Tower, Intel Xeon 3.2GHz x 2, 12GB DDR2 FB-DIMM, 640GB HD, Superdrive, Radeon HD 5770 1GB, OSX El Capitan 10.11 Intel Xeon Quad-Core X5482 3.2GHz x 2 CPUs "Eight Core" 12GB DDR2 FB-DIMM 800MHz Memory Kit 640GB HD & Superdrive Radeon HD 5770 1GB Graphics Mac OSX 10.11 El Capitan