No sound on board?

Hi folks.
Doing an installation of a new Gigabyte GA-81915G Pro board. (onboard video)
Got it in the tower with P4 2.8 CPU,
Gigabyte 128MB NX66T128D GEF6600 PCIEX video card,
(Extra vid card because of extreme video requirement by customer)
512 MB memory for now.
Boots good & have XP installed etc.
Only prob is that it has no sound.
In the setup there appears to be nowhere to activate it.
There is a setting to auto detect the AZALIA audio function. I've tried this
on & off.
Really it has audio onboard (C-Media (9880 CODEC (UAJ) ) & by all accounts
it should just "be there".
Any ideas folks?
In device manager it just isn't there so don't tell me to remove it &
reboot.
I've tried forcing the C-Media drivers into it but get "no hardware for
these drivers" & it exits.
Have unidentified hardware "in pci slot" that XP cannot find driver for
either on the driver disk or on Microsoft site.
Hope you can help?