Sony VAIO VGN-SR520G/B 13.3" Notebook (2.2GHz Core 2 Duo T6670 4GB RAM 500GB HDD DL DVD-RW Microsoft Windows 7 Professional 64-bit) Sony VAIO VGN-SR520G/B Core 2 Duo T6670 2.2 GHz 13.3-inch Notebook General Features: Durable magnesium alloy casing (just over 4 pounds with standard battery, approximate) Microsoft Windows 7 Professional 64-bit pre-installed w/CoA Intel Core 2 Duo T6670 2.20 GHz processor Intel Dual Core processor technology 4 GB DDR2 PC2-6400 memory (8 GB maximum supported)