hello, my computer doesn't have sound when I played music CDs or do anything. Normally, it should give out some sound when I turn on or off the computer, but my computer doesn't. It's not muted and my speakers don't have problems. I am using windows 2000. And after I check what sound card, it shows AC'97. Do you guys know what might be wrong? thank you.

Was the sound working before? If so what have you added to your computer since - software - hardware? Lots of things can cause sound to stop working. Does the sound require amplified speakers - if so, they may not be audible when the amp is off. Are you sure the speakers are in the right jack (e.g. some modems have a speaker jack)? For music cd's, there must be an audio cable connected from the cdrom drive to a sound card, or a connection on the mboard if you have onboard sound - connectors on both ends must be wired right (usually are by default because of proprietary connectors). Nothing else requires this cable. When you play an audio cd, can you hear it if you insert a headphone jack into the front of the drive? If you can't, the drive is fried.