I recently reformatted my computer
And everything works properly on my computer but there is no sound at all
Even when I turn the computer on, there is no sound
And I checked several times if the speaker is not connected
Properly..

Motherboard ID <DMI>
Dell Inc. Dimension 8400
Intel NetBurst
64 bit
200MHz(QDR)
800MHz
6400 MBps

PCI/PNP Audio:
Intel(r) 82801AA AC'97 Audio Controller [NoDB] PCI
Multimedia Audio Controller [NoDB] PCI



And I also checked
Sound,video, game controllers list
But there was no exclamations
In sound, video and game controllers

But there were like 5 exclamations
In other devices which are:
Ethernet Controller
Mutimedia Audio Controller
PCI Modem
Video Controller
Video Controller (VGA Compatible)

Please help me!:(

After I reformatted my computer I had somewhat the same problem and it was something wrong with one of my drivers. Don't quote me on this because I'm not sure but that's what was wrong with mine. :)

Do a search for AC97 audio drivers.