sound was working but then stopped..

I have a Creative AudioPCI (ES1371,ES1373) (WDM) and it was working until just about 2days ago and I dont understand why.. I tried the services.msc thing but that didnt work and I tried uninstalling and reinstalling but that didnt work either. can you help me? Here are the specs on my comp:
Windows XP Professional Service Pack 2 (build 2600)
Board: Intel Corporation D915GAG AAC89289-101
Serial Number: AZAG52100137
Bus Clock: 200 megahertz
BIOS: Intel Corp. EV91510A.86A.0444.2005.0429.2108 04/29/2005
Creative AudioPCI (ES1371,ES1373) (WDM)
Game Port for Creative

Sorry for having to create a new post..

Welcome to Windrivers Shounen

You are quite correct to start a new thread. Tacking onto other's threads when you have different hardware can be very confusing.

What puzzles me is that you have onboard Realtek Hi Definition Audio according to the motherboard specification.

The creative audio is a separate pci card? Does it show up in device manager?

Is there some specific reason your using the creative sound card over the onboard hd realtek.
I build a number of computers and realtek is a very good chipset for audio.
To start shutdown and remove the creative card and then boot up again to desktop. Then shutdown and re insert the creative but do it in a different slot
Using another slot will force a new install

well, its not me, my brother did it. I dont know why, but he said he disabled the other chip and used this one, and then it suddenly stopped working.. the winamp plays and everything but there's no sound... should I remove this chip and use the old one or remove the old one?

I would remove the pci card and use the onboard sound, yes.

Make sure that you have the computer unplugged from the mains power and that you discharge any static you have in your body before touching the pci card.