Operating systems Pre-installed (availability varies by region): Windows 8.1 Pro (64-bit)* Windows 8.1 (64-bit)* Windows 7 Ultimate (64-bit)** Windows 7 Professional (32-bit)** Windows 7 Professional (64-bit)** Windows 7 Professional (32-bit) (available through downgrade rights from Windows 8.1 Pro)*** Windows 7 Professional (64-bit) (available through downgrade rights from Windows 8.1 Pro)*** Windows 7 Home Premium (32-bit)** Windows 7 Home Premium (64-bit)** Windows 7 Home Basic (32-bit)** FreeDOS 2.0 Novell SUSE Linux Enterprise Desktop 11 Display 19.5" diagonal TN widescreen WLED backlit anti-glare LCD (non-touch) Resolution 1600 x 900 (16:9) Contrast 1000:12 Image brightness 250 cd/m2 Viewing angle (typical) R/L 170°, U/D 160° Processors9 Intel® 4th Generation Pentium® , Core™ i3, i5, i7 Processors Chipset Intel® H81 Express Memory15 1600 MHz DDR3 SDRAM; (2) DIMM slots enabling up to 16GB, dual channel memory support16 Internal storage17 Up to 1TB SATA hard drive; up to 1TB solid state hybrid drive; up to 256GB self-encrypting solid state drive; 500GB selfencrypting drive Removable storage1,18 Slim DVD-ROM drive, Slim SuperMulti DVD drive, Slim BDXL Blu-ray Writer drive19 Expansion slots (1) Mini PCIe half-length (used by optional wireless LAN module) Bays (1)3.5" internal; Supports one – 3.5" hard drive or one – 2.5" hard drive (HDD/SSD/SED/SSHD) (1) 5.25" external; Slim Line Optical Drive1 Ports and connectors Side: (2 )USB 2.0 ports, including (1) fast charging port microphone, headphone SD card reader (optional)1 Rear: 4) USB 2.0 ports; (1) DisplayPort video port; (1) RJ-45 Gigabit Ethertnet network connector; (1) RS-232 serial port; 3.5mm stereo line out jack Graphics Integrated Intel® HD Graphics20 Audio DTS Sound +™, Realtek ALC 3228 Audio, microphone and headphone jacks, stereo audio line out and integrated business-class speakers (2W x 2W) Webcam1 Optional integrated 1 MP webcam & dual microphone array; maximum resolution of 1280 x 7201 Communications Integrated Realtek RTL8151GH-CG GbE LOM 10/100/1000 Network Connection; Optional wireless LAN and wireless LAN and Bluetooth combo cards available1 Input devices1 USB keyboard, Wireless Keyboard and Mouse, USB CCID SmartCard keyboard, USB PS/2 Washable keyboard, USB Optical mouse, USB 1000dpi Laser mouse, USB PS/2 Washable Scroll mouse