8GB ( 1x 8GB Module ) DDR3 1333 MHz ( PC3-10600 ) DDR3 DIMM ( 240-Pin ) ECC RDIMM ( Registered DIMM ) 1.35V - DDR3 Low Voltage Compatible Equivalent for HP A0R58A, 731656-081, 604506-S21, 664690-001, 698889-001, 647875-B21, 605313-071, 647649-171, 647650-07H, 687460-001 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