I have an Acer Aspire 5100
Windows XP Professional x64 and Ultimate Ubuntu 2.0 x64
Perhaps the best solution is to check Windows Update.
Make sure you choose CUSTOM for your installation option.
Then check for HARDWARE updates.
After hours of trying to install, tweak and even REINSTALL OS!!!!

I finally realized that microsoft scans your system for hardware updates automatically!
I hope your search finally ends here!