A-Tech 8GB Kit (2X 4GB) DDR3 1333MHz PC3-10600E 2Rx8 240-pin ECC-Unbuffered DIMM for HP Workstation Z200 and Z400 – Server Memory Ram Modules at Amazon.com
4GB DDR3 1333MHz ECC Memory 2RX8 PC3-10600E 1.5V RAM Unbuffered for Server Workstation - Walmart.com