Hello BigR,
To enable your on-board audio, simply take the sound card out.
Sometimes your on-board audio will conflict with a third party sound card so you may have had to disable it in your BIOS. If you have disabled it in BIOS, just go into your BIOS and re-enable your on-board audio.
To get into your BIOS, just look at the Compaq splash screen and check for whatever key it tells you to hit to enter setup. Then hit that key. When you are in the BIOS, there should be an option that says on-board audio - Enabled/Disabled. Just set it to enabled, or auto...whichever option it gives you.
Hope that helps!
