Dell Optiplex 990 Desktop i7-2600 3.4GHz 500GB 8GB DVD+/-RW WINDOWS 7 PRO 64-Bit HD6450 Processor: Intel Core i7-2600, 3.40GHz; 4 Cores, 4 Threads; 6MB L3 Cache; Memory: 8GB DDR3 Installed; Hard Drive: 500GB 7200rpm 3.5" SATA Operating System: Windows 7 Professional 64-Bit Installed with Recovery / Reinstallation Partition and Certificate Of Authenticity;Q Optical Storage: CD/DVD+/-RW DL Super Combo; Power Supply: 250 Watt 80 Plus Gold Gaphics: ATI RADEON HD6450 1GB DVI Graphics Card; Audio: Integrated High Definition Audio Controller; Communication: Integrated Intel Gigabit Ethernet Controller 10/100/1000 Front I/O Ports: 4 USB 2.0, 1 Headphone / Audio Out, 1 Microphone / Audio In; CARD READER: SM ,xD, CF/MD, MA/PRO/DUO, SD/miniMMC,RS Rear I/O Ports: 6 USB 2.0, 1 DisplayPort, 1 VGA, 1 Audio Out, 1 Audio In, 1 Serial, 2 PS/2; PARRALLEL PORT ADD-ON CARD