OWC 128GB (2x64GB) DDR5 4800 CL40 ECC RDIMM 2Rx4 1.1V ThinkSystem SR635/645/650/655/665 V3

Server-specific ECC RDIMM kit

This 128 GB kit contains two 64 GB DDR5 4800 CL40 registered ECC modules built for Lenovo ThinkSystem SR635 V3, SR645 V3, SR650 V3, SR655 V3 and SR665 V3 servers. The 288-pin RDIMMs operate at 1.1 V and use a 2Rx4 organisation. They are not compatible with standard desktop motherboards or with unbuffered or load-reduced memory types.

Sustained load behaviour

Registered buffering places a register between the DRAM and the memory controller, reducing electrical load on the command bus during continuous operation. ECC circuitry corrects single-bit errors and detects multi-bit errors without halting the system. The 1.1 V JEDEC voltage keeps power draw stable across extended workloads in multi-socket server platforms.

DDR5 RDIMM interface limits

The DDR5 4800 PC5-38400 standard defines the maximum data rate and timing envelope for these modules; higher speeds or lower latencies require platform and firmware support beyond the JEDEC base specification. Mixing registered DIMMs with unbuffered or load-reduced DIMMs is not supported by the memory controller. Capacity expansion depends on the number of DIMM slots and the qualified memory population rules for each ThinkSystem model.