8GB ( 1x 8GB Module ) DDR3 1600 MHz ( PC3-12800 ) DDR3 DIMM ( 240-Pin ) ECC RDIMM ( Registered DIMM ) 1.5V - DDR3 Standard Voltage Compatible Equivalent for HP 647899-B212, 647651-181, 664691-001, 647879-B21, 647899-S21, 647651-081, 676812-001, 676490-181, 687462-001, 647899-B21 High performance Memory RAM upgrade designed for Server/Workstation Systems All modules undergo quality assurance testing to ensure dependable and reliable performance Please verify the supported memory (RAM) specifications of your system prior to purchase to ensure compatibility A-Tech provides a Lifetime Warranty for all orders & offers complimentary United States based Tech Support before, during, & after your purchase