16GB ( 1x 16GB Module ) DDR5 4800 MHz ( PC5-38400 ) DDR5 DIMM ( 288-Pin ) ECC RDIMM ( Registered DIMM ) 1.1V - DDR5 Standard Voltage Compatible Equivalent for IBM-Lenovo 4X77A77029, 4X77A81437 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