Lenovo ThinkCentre M81 Business Desktop (Intel Core i3, 8GB RAM, 500GB HDD, Windows 7 Professional, DVD-RW) (Certified Refurbished) This Certified Refurbished product is tested and certified to look and work like new. The refurbishing process includes functionality testing, basic cleaning, inspection, and repackaging. The product ships with all relevant accessories, a minimum 90-day warranty, and may arrive in a generic box. Only select sellers who maintain a high performance bar may offer Certified Refurbished products on Amazon.com Intel Core i3 Processor, 8GB DDR3 Memory, 500GB Hard Drive; DVD Rom, 8 x USB 2.0, 1 x VGA, 1 x Display Port, 1 x eSata port, RJ45, audio in, audio out, microphone jack; Slim/Small form factor Business Desktops & Workstations, Comes with mouse and keyboard; Windows 7 Professional 64-bit English (activation code sticker included on desktop case), free Windows 10 Professional upgrade.