I have the same onboard sound card on my motherboard. What I did when I did a fresh install of xp was, go to Microsoft update and check for optional updates. One of the options was the latest driver for Realtek AC'97. Give a shot.
If that doesn't work for you, try refromatting again. It shouldn't crash your machine when installing an audio driver. You may have a bad install on you hands.
Alright I tryed all of the above method's and not one have worked wen i put in the dislk i ran a upgrade install and when it got the Realtek it said '' sorry this has not passed windows logo testing" and crashed my comp....like before...