3DS RDIMM

A 3DS RDIMM is a registered dual in-line memory module (RDIMM) built from three-dimensionally stacked (3DS) DRAM, with several dies per package joined by through-silicon vias (TSVs). Stacking raises the capacity of each package without needing a denser die. On DDR4, Lenovo notes, 3DS took modules to 256 GB and 512 GB, against 64 GB with single-die packages.

Micron's 256 GB DDR5 RDIMM uses 3DS and is rated up to 9,200 MT/s. It draws 11.1 W, against 19.4 W for two 128 GB modules at 9.7 W each. Micron builds its 128 GB RDIMM without stacking, from monolithic 32 Gb dies. For that module, Micron claims up to 16% lower latency and up to 22% better energy efficiency than competing 3DS products.

Specify 3DS only when the slots cannot reach the target capacity with 128 GB modules, such as 2 TB in eight slots, which needs 256 GB modules. Then make every module 3DS, because 3DS and regular DIMMs cannot be mixed in one system.

Sources

Last verified October 7, 2026.