OWC 16GB DDR4 2666MHz ECC RDIMM Lenovo ThinkSystem SR670 SR850 SR860 SR950 ST550

Server memory upgrade

This 16 GB DDR4 2666 MHz ECC registered DIMM is built for Lenovo ThinkSystem servers including the SR670, SR850, SR860, SR950 and ST550. It targets administrators who need to expand capacity or replace failed modules in Xeon SP Gen 1 platforms. The module will not work in standard desktop computers and cannot be mixed with unbuffered memory.

Thermals and power

Operating at 1.2 V with CL19 latency, the module runs at standard DDR4 voltage without a heat spreader. Registered buffering reduces electrical load on the memory controller, helping keep power draw predictable in multi-DIMM configurations. No active cooling is required beyond normal server airflow.

Replacement scope

The DIMM replaces Lenovo part numbers 01AG618, 4X70P98202 and 7X77A01303 and is backward compatible with 2133 MHz and 2400 MHz slots. The upgrade is worthwhile when adding capacity to existing channels or swapping out slower modules in the supported ThinkSystem models. Buyers who need unbuffered memory or desktop compatibility should look elsewhere.