I recently got a new pc with an Asus P5K motherboard, after reformatting it the built-in sound card was not working anymore.
This is how I fixed it:
- From control panel, add/remove, remove these 2 softwares if they are installed, “Realtek High Definition Audio Driver” and “High Definition Audio driver Package - KB888111″.
- Restart Windows
- Get the latest Realtek drivers from here.
- Install it, and reboot.
- Should be working now!
I think this should work on all Asus Motherboards that have a built-in HD Realtek Soundcard.

