Page 28 (on bottom of manual page) or page 40 in PDF manual:
<i><b>Audio Setting (3 pin Audio_en)</b>
The onboard 6 channel audio chip may be enabled or disabled using these jumpers. The default, [1-2], enables the audio setting. Disable the onboard audio system if using a PCI audio card on any of the expansion slots.</i>
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If you are honest because honesty is the best policy, then surely your honesty is corrupt </b></font color=orange>