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 memory. OWC 32GB UPGRADE: Consists of a single 32GB DDR3L 1600 PC3L-12800 CL11 4Rx4 240-pin 1.35V ECC Registered DIMM Memory RAM Module Upgrade memory module compatible with Supermicro Motherboard models X9DRFF Series, X9DRFR Series, X9DRG Series, X9DRH Series And X9DRi Series. 100% COMPLIANT: JEDEC-Standard and ROHS Compliant. Warranty-Safe Upgrade. Designed and Tested to Meet or Exceed all Manufacturer OEM Specs. 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.