SH693UC#ABA-07 - HP Desktop HP Z400 Workstation Xeon Quad-Core 3.20GHz — Tech Network Supply LLC
CMS 8GB (2X4GB) DDR3 10600 1333MHZ ECC Non Registered DIMM Memory Ram Upgrade Compatible with HP/Compaq® Workstation Z400 Workstation for Server Only - B80 at Amazon.com
Hp Z 400 mixed ram - HP Support Community - 7621103