Apple Mac Pro "Quad Core" 2.66 A1289 MB871LL/A Quad Core Intel Xeon W3520@2.66GHz, 6GB DDR3 RAM, 1TB SATA HDD, NVIDIA GeForce GT 120 Video Card w/ 512MB memory, 18X DL "SuperDrive", OSX 10.8 Mountain Lion Dual Intel Xeon X5650 Six-Core Processors 2.66GHz (3.06GHz Turbo) 12 MB L3 Cache (Total of 12 Cores / 24 Threads) 16GB DDR3 1333Mhz ECC (8x2GB) 7TB (1x1TB 3x2TB Hard Drives RAID) 3.5" All 7200 RPM ATI Radeon 5870 1GB with DVI and 2x Mini Display Port OS X Mavericks 10.9