Operating System :Windows 10 Home & Pro MAR, Ubuntu Linux, Free DOS Chipset :Intel C226 Chipset Processors :Intel Xeon Processor E3-1200 v3 Family; 4th generation Intel Core i7 and i5 Memory Support :Up to 32GB 1600MHz ECC; up to 16GB 1600MHz non-ECC DDR3 memory; 4 DIMM slots Hard Drive :Up to two 3.5" SATA drives: 250GB, 500GB, 1TB, 2TB; Or up to four 2.5" SATA drives: 320GB, 500GB Removable Media :Up to two optional optical drives: DVD-ROM; DVD+/-RW; Optional 19-in-1 media card reader Expansion Bays :Two internal 3.5" bays; two external 5.25" optical bays Expansion Slots :One PCIe x16 Gen 3; one PCIe x16 Gen 2 wired x4; one PCIe x1; One PCI 32bit/33MHz Graphics :Support for one PCI Express x16 Gen 3 graphic card up to 150W (total for graphics) Audio :Integrated Realtek ALC269Q High Definition Audio Communications :Integrated Intel 82579 Gigabit Ethernet controller I/O Ports :Front: Two USB 2.0, Two USB 3.0, Mic/Headphones; Rear: Four USB 2.0, Two USB 3.0, VGA, DP, Serial. Two PS2, Audio I/O Input Devices :Dell Smartcard Keyboard; Dell Business Multimedia Keyboard Dell USB Optical Mouse; Dell Laser USB 6-Button Mouse Power :365W 90% efficient (80 Plus Gold Certified); 290W 65% efficient Dimensions :HxWxD: 14.17" x 6.89" x 17.13" / 360mm x 175mm x 435mm Weight :N/A