Interesting... not the least of which is you have 3! sound cards on that machine. Two of which look like they're currently installed at this point (your onboard sound card plus the Creative SB PCI 128 card).
Your current default sound device is set to Realtek (which is the onboard sound card).
> I don't know why onboard sound shouldn't work but try you can also change your default sound to the Creative SB sound card
Scroll down to the footnotes in [post=926040]Reference Guide to Help Setup and Troubleshoot Windows Audio and Sound Cards[/post]
>See Footnote #4 for how to change default playback device.
> If still problems, see footnote #3. Test your sound by checking Windows sounds. Do windows sounds work on either sound card?
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And if you STILL have sound problems, are you sure your external speakers are working?? Can you try pluging in a headset other external device??
Note you can also use the Dxdiag sound tabs to test sound from your playback devices (you should see 2 tabs - one for each device)