Mainstream gaming is all about 1080p. Monitors may be getting cheaper, making higher resolutions and multi-display setups ever more feasible, but Full HD is still sufficient for the average buyer. AMD knows it, and that's why morning's announcement of the Radeon HD 7790 came with a straightforward promise: the ability to play the latest games at 1080p with high detail settings for a maximum outlay of $149. Such claims can't be waved around without being t