Operating System :Windows 10 Home & Pro MAR, Ubuntu Linux, Free DOS Chipset :Intel C602 Processors :Intel® Xeon processor E5-1600 v2 with up to six cores Memory Support :Quad channel; Up to 128GB 1866MHz ECC or 1600MHz non-ECC DDR3 memory; 8 DIMM slots Hard Drive :SATA 7200RPM Up to 3.0TB, SATA 10K RPM Up to 500GB, SSD Up to 512GB Removable Media :Slimline options: DVD-ROM; DVD+/-RW; BD-RE; Optional 5.25" device: DVD+/-RW, 19-in-1 media card reader Expansion Bays :One external slimline optical bay; Two internal 3.5" hard drive bays; one external 5.25" bay; Expansion Slots :Two PCIe x16 Gen 3; one PCIe x16 Gen 3 wired x8 (HL); one PCIe x4 Gen 2; one PCIe x1 Gen 2; One PCI 32bit/33MHz Graphics :Support for two PCI Express? x16 Gen 2 or Gen 3 graphics cards up to 300W Audio :Integrated Realtek ALC269Q High Definition Audio Communications :Intel 82579 Gigabit Ethernet controller I/O Ports :Front three USB 2.0, One USB 3.0, Mic/Headphone; Rear: Three USB 2.0, Three USB 3.0, One Serial, Two PS2 Input Devices :USB: Dell QuietKey, Enhanced Multimedia, Smartcard Reader keyboard; Bluetooth Keyboard and Mouse USB: Dell two-button mechanical with scroll, Dell two-button optical with scroll Power :685W or 425W Dimensions :(HxWxD): 16.30 x 6.79 x 18.54"; 414 x 172.6 x 471mm Weight :N/A