OWC 8GB DDR3 1066MHz

OWC 8GB PC8500 DDR3 ECC 1066MHz DIMM Memory Compatible With Mac Pro 8-Core (Early 2009 - 2010) Model ID: MacPro4,1 MacPro5,1 : 2.9GHz Xeon X5570, 2.7GHz Xeon X5550, 2.3GHz Xeon E5520 / 2.4GHz Xeon E5620 Compatible With Mac Pro 4-Core (2009 - 2012) Model ID: MacPro4,1 MacPro5,1 : 3.3GHz Xeon W3580, 2.9GHz Xeon W3540, 2.7GHz Xeon W3520 / 2.9GHz Xeon X5570, 2.7GHz Xeon X5550, 2.3GHz Xeon E5520 / 3.2GHz Xeon W3565 Compatible With Xserve Xeon (Early 2009) Model ID: Xserve3,1 2.9GHz Xeon X5570, 2.7GHz Xeon X5550, 2.3GHz Xeon E5520, 2.3GHz Xeon E5520 International products have separate terms, are sold from abroad and may differ from local products, including fit, age ratings, and language of product, labeling or instructions.