foone🏳️⚧️ on Twitter: "ar in ##whitequark has alerted me that there's a "asus dimm.2" form factor, which is a way to hook up m.2 drives to special ram slots on ASUS motherboards.
DIMM2
8GB KIT (2 x 4GB) for HP-Compaq Workstation Series Z620 (ECC Registered) Z820 (ECC Registered). DIMM DDR3 ECC Registered PC3-12800R 1600MHz Dual Rank Server Ram Memory. Genuine A-Tech Brand. at Amazon.com