Model :HP Z400 Workstation TWR - Tower Operating System Info :NO OPERATING SYSTEM. THIS COMPUTER COMES WITHOUT THE OPERATING SYSTEM. The buyer will need to purchase and install his or her own Windows OS. Processor :Xeon W3505 @ 2.53 GHz Memory Installed :6 GB DDR3 Hard Drive :250GB Optical Drive :DVD-RW Chasis : Dimensions : 17.70" high x 18.00" wide x 6.60" deep System Weight : 43.00 lbs Warranty : 365 days

Model :HP Z400 Workstation TWR - Tower Operating System Info :NO OPERATING SYSTEM. THIS COMPUTER COMES WITHOUT THE OPERATING SYSTEM. The buyer will need to purchase and install his or her own Windows OS. Processor :Xeon W3505 @ 2.53 GHz Memory Installed :6 GB DDR3 Hard Drive :250GB Optical Drive :DVD-RW Chasis : Dimensions : 17.70" high x 18.00" wide x 6.60" deep System Weight : 43.00 lbs Warranty : 365 days