4GB ( 1x 4GB Module ) DDR3 1333 MHz ( PC3-10600 ) DDR3 DIMM ( 240-Pin ) ECC RDIMM ( Registered DIMM ) 1.5V - DDR3 Standard Voltage Compatible Equivalent for HP 591750-071, 595424-001, 649940-001, 595096-001, 593911-B21, AM230A, 593339-B21, 591750-371, 008011-130, 593339-TV1 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