With a 7.1 surround sound model card you can still set the speajer setting to 5.1. You can even set it to 2 1/2 as a rule on most sound card softwares. For a large area you may eventually want a 7.1 set of speakers. For a limited amount of space like on the average desktop or even computer desk the 5.1 is quite adequate. There's where the quality of card and speakers plays a role!