nVidia 680i SLI mobo and microphone

Hey all,
im having a problem with my microphone , and i think the problem is coming from the motherboard.(680i SLI)
i built my own rig ... and i was thinking that when i plugged all the connectors to the motherboard ,i misplaced an audio connector, could it provoke the mic not to work???cause everything else is working properly.i got 2 headphones jacks. and both are not working....
second thought is the OS .. im using Vista ,, could the malfunction come from the operating system?....

PS :im currently using the mic incorporated in the webcam;;it makes a poorsound....

it really bothers me

Thanks.