I was giving the short story :
The sound system works fine when I am using WinXP.
I used another HDD installed Vista - on the same system - and try various audio drivers - no sound !
When I play an audio CD then click the speaker icon on taskbar the volume bar danced in sync with the music !
Enable it in the Bios if you have not done so already. Done
Test your speakers on another computer. it works when in WinXP
Check "Device Manager" for exclamation points. no yellow mark
Check the volume on the computer and the mute button. not muted
The issue is with Vista. Windows XP and previous OSes used Direct 3D Sound to communicate with the sound card.
Windows Vista throws out D3D Sound in favor of OpenAL instead. Therefore, only sound drivers that are compatible with OpenAL will work with Vista.
If you want to use integrated sound, then you will need to wait until Microsoft releases some type of generic sound driver that will work with integrated audio (unlikely) or you need to wait until Realtek releases an OpenAL compatible driver.
Your only other choice is a separate audio card like the Sound Blaster X-Fi. Speaking of Sound Blaster cards, they will work with Vista, but only on a very basic level; EAX will not be supported. Creative Labs will release or has released Vista compatible drivers only for the X-Fi series of sound cards that will make them fully functional with Windows Vista.
Last I heard, Creative Labs will not release Vista compatible drivers for the Audigy series or older sound cards.
May be Gigabyte & Realtek are not aware of the D3D and OpenAL
stuff. Because they both have posted Vista drivers for realtek onboard sound on their websites and lead me to spend 29 days since install trying to 'force' sound out of the system.
I have extended activation for another 30 days, meanwhile will source on local market for a suitable sound card.