Quote: Originally Posted by
chilloh 
i have a 64-bit
Is this the driver you downloaded :
GeForce Release 178?
Try opening "Control Panel" -> "Programs" -> "Uninstall a Program", and see if there is an uninstall for any previous versions of the driver, and then uninstall that driver.
If the new driver even then fails to install, go to "Control Panel" -> "Hardware and Sound" -> "Device Manager". Open the "Display Adapters" section by clicking the + icon. Right-click on your display driver and select "Uninstall". Reboot. Install the driver you downloaded.
If even then you fail with the drive installation, then either you DON'T have an nVidia 8600GTS and you have the wrong driver, or there is some problem with the hardware itself and would need to be replaced.