Operating System : Windows 10 Home & Pro MAR, Ubuntu Linux, Free DOS Chipset : Intel Q77 Express Chipset Processors : Intel Core i5 3rd Gen Memory Support : Four DIMM slots, Non-ECC dual-channel 1600MHz DDR3 SDRAM, up to 16GB Hard Drive : 3.5": up to 1TB 7200 RPM SATA, 2.5": up to 500GB 7200 RPM SATA, 500GB Hybrid, 128GB SSD Removable Media : DVD+/-RW; DVD-ROM Expansion Bays : Two (2) internal 3.5", Two (2) external 5.25" Expansion Slots : One (1) PCIe x16, One (1) PCIe x16 (routed as x4), One (1) PCIe x1, One (1) PCI Graphics : Integrated Intel HD Graphics Audio : N/A Communications : Integrated Intel 82579LM Ethernet LAN 10/100/1000 I/O Ports : 4 External USB 3.0 ports (2 front, 2 rear) and 6 External USB 2.0 ports (2 front, 4 rear), VGA, DP, 2 L/I, 2 L/O Input Devices : Dell USB Entry Keyboard, Dell Multimedia Pro Keyboard, Dell Smartcard Keyboard, Dell USB Optical Mouse, Dell Laser Mouse Power : 275W Dimensions : 36 x 17.5 x 41.7 cm Weight : 9.4 kg