Dell OptiPlex 990 SFF Core i7 3.40GHz 4GB WINDOWS 7 PRO 64-Bit HD5450 DVD-ROM Processor: Intel Core i7-2600 3.40GHz; 4 Cores. 8 Threads; 8MB L3 Cache; Memory: 4GB DDR3 Installed; Hard Drive: 500GB Operating System: Windows 7 Professional 64-Bit Installed with Recovery Partition and Certificate Of Authenticity; Optical Storage: DVD-ROM; Power Supply: 240 Watt Graphics: Integrated Intel HD Graphics Controller; Audio: Integrated HD Audio Controller; Communication: Integrated Gigabit Ethernet Controller Front I/O Ports: 4 USB 2.0, 1 Headphone / Audio, 1 Microphone / Audio Rear I/O Ports: 6 USB 2.0, 1 DisplayPort, 1 VGA, 1 Audio Out, 1 Audio In/Out, 1 Ethernet (RJ-45), 1 Serial, 2 PS/2