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 1TB UPGRADE: Consists of 4pcs of 256GB DDR4 3200 PC4-25600 CL22 8Rx4 Octal-Rank 288-pin 1.2V ECC Registered DIMM Memory RAM Module Upgrade compatible with Supermicro Motherboard models H11SSL-C, H11SSL-i, H11SSW-iN, H11SSW-NT And H12SSL-C. Compatible with Samsung M393ABG40M52-CAE, Hynix HMAT14JXSRB120N and HMAT14JXSRB122N, and Supermicro MEM-DR425MI-ER32 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. INDUSTRY LEADING: Consumer-friendly Advanced Replacement Program and Limited Lifetime Warranty, which includes Free Tech Support by Other World Computing.