12GB(6X2GB) DDR3 PC3-10600R 1333MHz DTM64304C Server Memory RAM | eBay
Kingston HP 12GB 3x4GB DDR3 1333MHz ECC at Amazon.com
EDGE Tech 12GB DDR3 SDRAM Memory Module – Natix
Crucial 12GB DDR3 SDRAM Memory Module (CT3KIT51272BB1339) at Amazon.com
CMS 12GB (3x4GB) DDR3 10600 1333MHZ ECC Non Registered DIMM Memory Ram Upgrade Compatible with HP/Compaq® Workstation Z600 B3 Series DDR3 ECC for Server Only - B81 at Amazon.com
CMS 12GB (3x4GB) DDR3 10600 1333MHZ ECC NON REGISTERED DIMM Memory Ram Upgrade Compatible with HP/Compaq® Workstation Z600 B3 SERIES DDR3 ECC For Server Only - B81 - Newegg.com
Solved: CPU-Z said 12GB ram, Windows said 4GB - HP Support Community - 5621238