For Windows 98, you need to install 2 drivers BEFORE you install the display adapter driver.
First, download and install the chip-set drivers for the specific chip-set on the motherboard.
(Intel or VIA)
Specifically, you need the AGP mini-port driver.
Next, download and install DirectX (from Microsoft). I believe that the driver for the Rage II series only supports DirectX 7.
(Check the readme file from ATI to verify which version of DirectX is required.)
DO NOT INSTALL A NEWER VERSION OF DIRECTX THAN IS SUPPORTED BY THE ATI DRIVER!!!
Then, you can install the ATI driver.
Chas