I installed a new hard drive in a Dell E1505 laptop for my daughter, and when installing the drivers, I didn't notice that there was an order in which to install them. Everything works fine except there is no sound. A beep when I hit a wrong button, but no sound. I have read some forums, and thats how I found out that there is an order in which to install the drivers. I have tried to install these several times, but nothing works. I even tried to uninstall the drivers, but it says I don't have access or won't let me erase them. Today I did a roll back on the audio driver, and it tells me I need "Sigma Tel High Definition Audio WDM Driver Disk". I am trying to download it and burn it but am haveing a hard time finding this perticular driver. I have all the drivers that dell says I need on a disk I burned, just cant seem to find a way to get rid of the old drivers so I can reinstall them in the correct order, Can you help me?