Enabling onboard sound with a sound card

Hi, I fly MS FSX and I want to be able to chat to ATC with my headphones and then hear the engine noises coming out of my speakers and sub-woofer.

I have a soundcard and my motherboard has onboard sound. I can't find the bios setting to turn it on and I can't see any hint of it anywhere on the computer. Can someone help me get the on board sound going?

My computer is homebuilt, I recently installed Windows 7 pro 64bit. Specs in profile.

Thanks

In your bios it is under "Integrated Peripherals" and called "Azalia Codec".

P.S. What you want to do will only work if the chat program you want to use allows you to choose from more than one audio device, if it doesn't then it will only use the Windows default device.

In my bios that azalia codec has either the option of auto or disabled. It was already on auto and whatever that means I don't have it working. Yes, FSX is designed to take two sound sources. Any further ideas how to get it into life?