How do you benchmark a sound card?
Well, we can show that there's little to be gained in terms of frame rates by offloading sound cycles from the CPU, and Rightmarks' Audio Analyzer (RMAA) can give us a technical overview of what's going on inside. Ultimately, though, audio is subjective, and different ears will like different things.
Far Cry 2 - Frames per second (higher is better)
RMAA total harmonic distortion
RMAA Dynamic range