OWC 4 GB Single DDR3-1333 ECC Unbuffered DDR3 DIMM

Macintosh 4 GB Single DDR3-1333 ECC Unbuffered DDR3 DIMM Dual Processor 2.66GHz and 2.93GHz systems Only DDR3-1333, 8 memory socketsuse 3 modules for triple channel performanceNOTE: Maximum under OSX 10.6-10.8 is 96 GB,and 10.9 and above supports 128GB. 16GB ECC Registered modules require that all installed modules be of this same matching part. Other modules are not supported for use with this kit and need to be removed when this kit is added.