OWC 128GB DDR4 2666 PC4-21300 CL19 8Rx4 288-pin 1.2V ECC Registered RDIMM Memory Upgrade

Server-grade ECC registered DIMM

This OWC module delivers 128GB of DDR4 ECC registered memory rated at 2666 MT/s with CL19 latency and 1.2V operation. It is built for Lenovo ThinkAgile HX1320, HX1321, HX2320, HX2321 and HX3320 systems running Xeon SP Gen 1 processors. The single 288-pin RDIMM uses an 8Rx4 organisation to provide high-density capacity for virtualisation and database workloads.

JEDEC DDR4-2666 interface limits

The PC4-21300 standard caps transfer rates at 2666 MT/s, so this module will not exceed that ceiling even if the platform supports faster speeds. Backward compatibility with 2133 and 2400 MT/s buses is built in, allowing the DIMM to clock down automatically when installed in slower channels. Registered buffering adds a cycle of latency versus unbuffered DIMMs, a trade-off required for signal integrity at high module counts.

288-pin registered form factor implications

The 288-pin RDIMM keying prevents insertion into desktop UDIMM slots, so it cannot be used in standard consumer motherboards. No heat spreader is fitted, relying on chassis airflow for cooling in dense server configurations. Mixing this registered ECC module with unbuffered or load-reduced ECC DIMMs is not supported and will prevent the system from posting.