HP 647646-171 COMP 4GB DDR3-1333MHZ ECC SRX4 RDIMMAddOn 4GB DDR3 SDRAM Memory Module 4 GB (1 x 4GB) DDR3 1333 PC3 10666 DDR3 SDRAM 1333 MHz Single rank Memory 1. 35 V ECC Registered 240 pin DIMM Lifetime Warranty VPN: 647646 171 AM SKU: RSC510767 UPC: 195285045577 DIMM 4 GB of memory to heighten your computer's performance DIMM 4 GB memory allows you to have more programs open at a time 1333 MHz speed to execute routine softwares at a steady pace