HP 647647-171 COMP 4GB DDR3-1333MHZ ECC 1.35V SR RDIMMAddOn 4GB DDR3 SDRAM Memory Module 4 GB (1 x 4GB) DDR3 1333 PC3 10664 DDR3 SDRAM 1333 MHz Single rank Memory CL9 1. 35 V ECC Registered 240 pin DIMM Lifetime Warranty VPN: 647647 171 AM SKU: RSC331615 UPC: 821455579602 DIMM 4 GB of memory makes a perfect symmetry with your latest model processor and boosts up your computer's performance Up to 1333 MHz memory speed to manage your routine softwares with pace and accuracy DDR3 1333 PC3 10664 interface