Exterior
The exterior finish differs on both systems.The PS3 Fat features a slick and glossy black exterior compared to the Slim's more muted and matte black finish. Some users of the Fat model have complained about smudges and fingerprints that display more prominently on the system's glossy finish.
Backward Compatibility
Another difference between the two models exists in backward compatibility, a feature previously touted by Sony. Backward compatibility offers gamers the ability to play PlayStation 2 titles on a PS3. The PS3 Fat offers this feature, but the Slim doesn't. The Slim model does offer users the option to play even older PlayStation 1 games.
Dimensions &Weight
The PS3 Slim and Fat differ in weight and size. The PS3 Fat weighs 11 lb. compared to the Slim's 7.7 lb. In addition, Sony reduced the physical dimensions of the PS3. The PS3 Slim is 11.42 inches wide, 11.42 inches deep and only 2.56 inches thick. The heavier PS3 Fat is 3.86 inches thick, 12.81 inches wide and 10.79 inches deep.
Memory/Speed/Power
Both consoles differ in power consumption. The PS3 Slim uses less power than the PS3 Fat, at 250 watts, compared to the Fat's 280 watts. The PS3 Slim offers a larger storage capacity of 120 gigabytes, while the PS3 Fat sports an 80 GB hard drive. Sony also changed from a 90 nanometer (nm) processor made by IBM to the 45nm processor in the PS3 Slim.
Additional Features
Both models feature two USB ports, composite video cables and support Wi-Fi connectivity. Sony also includes an Ethernet cable with the PS3 Fat console but not with the Slim.