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 32GB UPGRADE: Consists of 2pcs of 16GB DDR3L 1600 PC3L-12800 CL11 2Rx4 240-pin 1.35V ECC Registered DIMM Memory RAM Module Upgrade compatible with Cisco UCS models B200 M3, B22 M3, B420 M3, C22 M3 And C220 M3. 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 Cisco part numbers UCSMR1X162RYA, UCSMR1X162RYARF and UCSMR2X162RYE.