Microphone Not working

I own a Dell inspiron 1501 laptop. My microphone was won't pick up sound
unless you scream and even still
you can hardly hear it. I tried turning up the volume and boost all the way,
didn't work. I even bought a new microphone and still, same problem. PLEASE
HELP! I have done the voice recognition and still it barely reads the
microphone. what can I do to make Vista recognize this microphone. I have
two sets of headphones and it does it with both.

ERIC
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