OWC 64GB (4x16GB) DDR3L 1600 CL11 ECC Registered RDIMM 2Rx4 1.35V memory upgrade

Server Memory Upgrade Kit

This 64GB kit contains four 16GB DDR3L 1600 CL11 registered ECC RDIMMs built for Lenovo System x3300 M4, x3500 M4, x3530 M4, x3550 M4 and x3630 M4 servers. Each module runs at 1.35V with a 2Rx4 organisation and fits the 240-pin DDR3 slots in those platforms. The modules are new and intended for workstation or server workloads that require error-correcting registered memory.

Replaces Lenovo Parts

The kit replaces Lenovo part numbers 0C19535, 46W0671 and 46W0672, letting administrators refresh or expand memory without sourcing discontinued OEM modules. The upgrade is worth it when the existing configuration uses smaller RDIMMs or when empty slots are available and the workload benefits from additional capacity. It cannot be mixed with unbuffered DIMMs and will not work in standard desktop computers.

Capacity And Headroom

Four 16GB modules provide 64GB total, giving headroom for virtualisation hosts, database buffers or large in-memory datasets on the supported Lenovo systems. The registered design helps signal integrity at this density, while ECC protects data integrity under sustained load. Systems limited to lower maximum memory per socket or fewer DIMM slots will not be able to use the full kit.