If that still did not help, do the following.
1. Check to make sure that your speakers have power (plugged into the wall).
2. Ensure that speakers are plugged into the correct jack on the sound card.
3. Ensure that the speakers aree turned on and that the volume know is
turned up.
Sorry about the first 3 steps, but I have seen it before.
If still no sound,
4. Right click your "My Computer" icon. Left click "Properties".
5. Left click the "Hardware" tab. Left click the "Device Manager" button.
6. Go down to "Sound, Video, and Game Controllers" and see if anthing under
that tree has a red "X" or yellow "!". If there is an "X", than try to right
click that item and click on "Enable". If there is an "!" then your driver
probably needs reloaded.
Hope that helps,
Aaron