How to change boot screen P4S333

Can someone tell me how to change the post screen on Asus P4S333.Also I cant seem to get the voice perompts to work.I am using a PCI sound card(Hercules GTXP)..Thanx!

Allso can i not get it to work with a PCI Card i have a Hercules Fortissimo II Gamesurround, i can only get it to work with the onboard card

So i´m all so lost

And i really want it to work with my Hercules to