A-Tech 32GB Replacement for HP P07646-B21 - DDR4 3200MHz PC4-25600 ECC Registered RDIMM 2Rx4 1.2V - Single Server Memory RAM Stick (P07646-B21-ATC) at Amazon.com
First Single 32GB DDR4 RAM Modules Spotted for Sale | eTeknix
Lenovo 32GB, DDR4, 3200MHz, Single Stick (4ZC7A15122)
Kingston 32GB, DDR4, 3200MHz, SODIMM, Single Stick (KCP432SD8/32)