ThinkCentre M58 USFF Pentium Dual Core 2.7GHz 4GB 250GB DVD-RW WINDOWS 7 PRO 64-Bit Processor: Intel Pentium Dual Core E5400 2.70GHz; 2 Cores, 2 Threads, 2MB L2 Cache; Memory: 4GB DDR3 SODIMM Installed 2 Slots; Hard Drive: 250GB 3.5" SATA Operating System: Windows 7 Professional 64-Bit Installed with Recovery / Reinstallation Partition and Certificate Of Authenticity; Optical Storage: CD/DVD+/-RW DL Super Combo; Power Supply: External 130 Watt AC Adapter (included) Graphics: Integrated Intel HD Video Controller; Audio: Integrated High Defintion Audio Controller; Communication: Integrated Intel Gigabit Ethernet Controller 10/100/1000 Front I/O Ports: 2 USB 2.0, 1 Headphone/Audio Out, 1 Microphone/Audio In Rear I/O Ports: 6 USB 2.0, 1 DisplayPort, 1 VGA, 2 Audio In, 1 Audio Out