Systems with quad SLI allow to turn on 32x antialiasing, the maximum level possible today, or to play the latest games in 2560×1600 resolution with all the quality improvement features activated. According to benchmark results obtained by MVKTech, four GeForce 7900 graphics processors may not only provide only slight performance advantages over two of such chips, but may even degrade performance, unless eye-candy settings are activated. I would think that this is most probably due to the increased CPU overhead when running “4” cards.