OWC 5R6D54R4128G 128GB DDR5 5600 CL46 4Rx4 ECC RDIMM memory upgrade

System-specific server memory

This OWC module delivers 128GB of DDR5 ECC registered memory in a single 288-pin RDIMM. It is built for Supermicro SuperServer platforms including the SYS-611C-TN4R and several SYS-621BT models. The registered design adds a buffer that stabilises heavy multi-DIMM configurations. Workstations and standard desktops cannot use this module.

JEDEC-standard registered build

The stick runs at 5600 MT/s with a CAS latency of 46 and operates at 1.1V. It carries a 4Rx4 organisation and has no heat spreader, so it fits tight server DIMM slots without clearance issues. ECC circuitry corrects single-bit errors on the fly. Mixing this registered DIMM with unbuffered or load-reduced modules is not supported.

Capacity jump for dense workloads

A single 128GB RDIMM lets you reach high memory totals using fewer slots, which is useful when upgrading older SuperServer units or populating a new build economically. The jump is worth it when your applications demand more addressable memory than smaller RDIMMs can provide. Buyers who need unbuffered ECC or consumer DDR5 should look elsewhere.