ECC REGISTERED UPGRADE: This type of memory is used in Workstations and Servers. It will NOT be compatible with standard desktop computers. Also, it cannot be mixed with UNBUFFERED -or- ECC LOAD REDUCED memory. OWC 128GB UPGRADE: Consists of 2pcs of 64GB DDR4 3200 PC4-25600 CL22 2Rx4 288-pin 1.2V ECC Registered DIMM Memory RAM Module Upgrade compatible with Supermicro Motherboard models H12SSL-CT, H12SSL-NT, H12SSW-iNR And H12SSW-NTR. INDUSTRY LEADING: Consumer-friendly Advanced Replacement Program and Limited Lifetime Warranty, which includes Free Tech Support by Other World Computing. MAXIMIZE YOUR SERVER: With OWC's ECC Registered Server Memory, you will extend the life of your old infrastructure or save money when building a new one. Replacement for Supermicro part numbers MEMDR464LCL02ER32 MEMDR464LCL03ER32 MEM-DR464L-CL05-ER32 MEMDR464LHL02ER32 MEMDR464LHL03ER32 MEMDR464LSL01ER32 MEMDR464LSL02ER32 MEMDR464MCER32.