Operating System :Windows 7 Home & Pro. MAR, Windows 10 Home & Pro MAR, Ubuntu Linux, Free DOS Chipset :Intel® 5400 Processors :Quad-Core Intel® Xeon? Processor 5400 or Dual-Core Intel® Xeon? Processor 5200 Memory Support :Eight (8) DIMM slots DDR2-667MHz FB-DIMM. Up to 32 GB Memory capacity Hard Drive :80GB to 1TB SATA 3.0-Gb/s, 73GB to 450GB SAS Drives Removable Media :16X DVD-ROM Drive, SATA 48X CD-RW/DVD-ROM Combo Drive, SuperMulti DVD+/-RW LightScribe Drive Expansion Bays :External: Two (2) 5.25-inch, One (1) 3.5-inch, Internal: Two (2) 3.5-inch Expansion Slots :2 PCI Express x16 Gen2 Graphics Bus, 2 PCI, 2 PCI Express x8 (x4) Graphics :N/A Audio :High Definition Integrated Realtek ALC262 Audio Communications :Integrated Broadcom 5755 Gigabit LAN I/O Ports :Front: Two (2) USB 2.0, Headphone/Mic, Rear: Five (5) USB 2.0, 2 PS2, Serial, Audio I/O Input Devices :Standard Keyboard (USB or PS/2) Mouse (USB or PS/2) Power :650 watt 80 PLUS high efficiency power supply Dimensions :N/A Weight :N/A