https://wccftech.com/amd-3d-v-cache-technology-in-development-for-years-seen-in-ryzen-9-5950x-sample/

A few months ago, AMD released information on their new technology for their Ryzen CPUs. AMD's 3D V-Cache technology takes up to 64 megabytes of additional L3 cache & stacks it on top of Ryzen CPUs.

Data for modern AMD Zen 3 CPUs show that through their design to having the accessibility to allow for the 3D cache to be stacked from the beginning. This proves that AMD has worked on this technology for several years.