Realtek audio driver problems. I am desperate

Hi. I have a Realtek HD audio device and i also have the cd that came with the laptop with all the drivers but i can't install the audio driver, it says:Microsoft Bus Driver should be loaded in your system before installing Realtek HD Audio driver.
I read a lot of toppics on this problem but still can't get it fixed. I tried the "ptaches" or fixes like: kb888111xpsp2 etc. and after i tried to install the sound driver but still doesn't work. Now i am formatting my entire hdd and trying to get it from scratch so please help me. Windows is newly installed and only the graphics card driver, and ethernet, directx... so the basics will be installed. I am trying to fix this problem for 3 days

 

Okay, got it fixed. i had to unistal from device manager the pci bus first and then add the fix and the driver