Thank you for describing the details of what helped you, JKEerie.
It's interesting that they suggest not using the reference drivers.
It used to be that it wasn't even possible to install anything but the laptop drivers from the laptop manufacturer on a laptop -- the install simply stopped if the installer didn't detect the appropriate hardware.
Damaged drivers often require a complete uninstall by something like Driver Cleaner. Simply updating the drivers won't get rid of damaged files if both sets of drivers use the same damaged file.
If you want to know what has to be done to completely remove drivers, someone posted a manual procedure herehttp://forums.guru3d.com/showthread.php?t=379461
As you can see, it's not just a matter of deleting files. There are also many registry entries. This is why people use tools like Driver Sweeper -- quicker to use and less prone to error.
ATI used to have their own driver removal tool that you could download from their website, but they seem to be relying on outside sources now -- maybe because tools like Driver Sweeper worked better than their own tool.