The Lenovo ThinkCentre M91p is a premium enterprise-class desktop computers optimized for high performance and manageability..Windows 10 Professional 64bit.4GB Memory, 250GB Hard Drive, SuperMulti Double Layer Drive.18 Month Warranty.Integrated Intel Graphics Media Accelerator HD.5 x DisplayPort, 1 x LAN (Gigabit Ethernet), 8 x USB 2.0, 1 x VGA, 1 x audio line-in, 1 x audio line-out, 1 x headphones, 1 x microphone, 1 serial.Refurbished Lenovo ThinkCentre M91p SFF Intel Core i5 3.0GHz, 4GB RAM, 250GB Hard Drive, Windows 10 Pro