HP 8GB (1x8GB) Dual Rank x8 DDR4 2133 MHz 288-pin DIMM RAM Module SDRAM (726718-B21 ) at Amazon.com
8GB (1x8GB) DDR4-2133MHz PC4-17000 2Rx8 1.2V SODIMM Laptop Memory by NEMIX RAM at Amazon.com
A-Tech 8GB Replacement for HP 759934-B21 - DDR4 2133MHz PC4-17000 ECC Registered RDIMM 2rx8 1.2v - Single Server Memory Ram Stick (759934-B21-ATC) at Amazon.com