I would first like to give credit and thanks to the following post:
no sound after i got a new graphics card.
After spending several days and many, many hours i found this post and fixed my problem. I hope my post will also help those that also come across this problem.Yes, knowing what hardware you actually have would have been helpful,
but that's OK. Before you go and buy a PCI sound card, go into your BIOS
and change your default graphics card from onboard to AGP (or PCIe,
whichever you have). While you're in there, make sure the onboard sound
Accessing the BIOS
How to access/enter Motherboard BIOS
UKT Support - How to Bypass BIOS Passwords
How to clear an unknown BIOS password.
Elephant Boy Computers
MS-MVP Windows - Shell/User