Mac Pro X1900 661-5452 R580,V2 Graphics Card 2-2.66-3GHz Quad - 3GHz 8-Core A1186 NB-2146W EEE code: XXN,YY2, Apple part number: 661-5452, Compatible models: A1186-2006-MA356LL/A, A1186-2006, A1186-2006, Compatible Mac info. : 2.66GHz Quad-Core Mac Pro , 3.0GHz Quad-Core Mac Pro , 3.0GHz 8-Core Mac Pro, 661-5452 R580,V2 Graphics Card - Mac Pro 2-2.66-3GHz Quad - 3GHz 8-Core A1186 EEE code: XXN,YY2