It looks like Intel's upcoming Alder Lake-S CPUs are going to be the first to benefit from the DDR5 RAM standard. ADATA is already collaborating with motherboard makers like Gigabyte and MSI to ensure compatibility for the "latest Intel platforms." Expect to see DDR5 RAM modules with up to 64 GB capacity and up to 8400 MT/s speeds launching in the second half of 2021.
https://www.notebookcheck.net/ADATA-to-launch-64GB-DDR5-8400-RAM-modules-for-Intel-s-upcoming-Alder-Lake-S-CPUs-in-2H-2021.513894.0.html