A quick check in the Device Manager will reveal the lack of some items, such as the “Via CPU to AGP Controller.” What’s worse is downloading and installing the latest Via Drivers won’t help under normal circumstances. This guide will get you the controller back and increase your framerates.
1. Download the latest Via 4-in-1 drivers here - http://www.viaarena.com/?PageID=2#4in1
2. Navigate to wherever you saved the drivers, and unzip them to a folder.
3. Open the folder and find the Setup.exe. Right-click it and choose Properties.
4. Click the Compatibility Tab.
5. Check the box labeled “Run this program in compatibility mode for: ” Choose Windows 2000 from the drop down list.
6. Click “Ok” to close the dialog.
7. Double-click the setup and install the drivers as usual.
8. When you reboot, you’ll notice the “Via CPU to AGP Controller” in your device manager, as well as a few other Via items that weren’t there before.
This works because, ultimately, XP is running Windows 2000’s engine under the hood. Hopefully Via will resolve this driver issue in the future, but in the meantime, this works quite well.