recording off of sound card

Several weeks ago before my computer crashed, I had no problem recording directly off the soundcard.
I have Windows XP. My soundcard is Sigma Tel Audio. Another choice under sound cards is Microsoft Sound Mapper.
I have reformatted my hard drive and reinstalled Win XP and Audacity. For some reason now, I can not get Audacity to record off the soundcard. Interestingly enough, the sound bars in the record area indicate that the sound is going through Audacity,
but when I hit the record button, nothing is being recorded. I’ve done everything I can think of without luck. Can anyone help?

It should be possible using the Audacity toolbar drop-downs to select Stereo-Mix, WAV Out, What-U-Hear or one of those to record whatever the computer is playing. You also have to select your sound card to make sure the captured show plays to your speakers. You have to hit both of them.