1. Optimus only support Win7 32/64bit.

2. if you need to uninstall Optimus VGA driver, please uninstall NVdia VGA driver first, then uninstall Intel VGA driver.

3. some XP driver need Microsoft .NET Framework 3.5 Service pack 1, please download it from
   http://www.microsoft.com/downloads/details.aspx?FamilyId=AB99342F-5D1A-413D-8319-81DA479AB0D7&displaylang=en

4. Audio driver must be installed before VGA driver in XP, or the HDMI audio will not be installed properlly.