https://www.pcgamer.com/how-would-you-like-a-512gb-ram-module-in-a-future-pc/

When Intel first talked about 3D XPoint Technology back in 2015, we heard claims of it reaching 1000X the performance of NAND memory. The problem with such a claim is that even the fastest PCIe interface can't come anywhere near that figure. Since Optane drives first became available, there have been rumblings that we'd see 3D XPoint make its way into some form of server DIMM. That product now has a name: Optane DC Persistent Memory, which is a mouthful, so I'm going to call it Optane DC PM.

As the name implies, Optane DC PM is for the datacenter—we're not likely to see this in desktops or laptops any time soon. The form factor looks the same as a regular DIMM, and each Optane DC PM module can hold up to 512GB. For certain workloads, Optane DC PM is likely to be a far more cost-effective solution than adding more RAM and/or servers, and it enables up to 3TB of 'memory' per server node. Also, note that the platform is stated as "future Intel Xeon scalable processors," so Optane DC PM isn't available yet.