Sound quality: Signal/noise ratio
We use the loopback test in Rightmark Audio Analyzer, and connect the input to the output of the onboard soundcard. First we look at the signal-to-noise ratio, and Gigabyte convincingly takes the crown with its G1.Sniper 5 motherboard and the Creative Sound Core3D chip. It's expensive, but you get what you pay for.
All of the boards with the new Realtek ALC1150 codec score really well here, with more than 90 dB(A). Boards with the older Realtek chips are generally around 82 dB(A).