790FX boards run at 4w idle and 10w load...so they run very cool and consume less power compared to say the nforce chipsets. Also you get features like HT3.0, PCI-E 2.0, AMD Overdrive, Quad Crossfire, better Phenom support and in most cases better Overclockability. If those features don't affect you then theres no reason to upgrade- as has been said upgrading motherboards is usually for feature sets not 'performance gains' although there can be larger gains with things like HT3.0.