In the game's "Video Settings", set the "Maximum Texture Size" to 256 or 128. Set the resolution no higher than 1024x768. Check the "Preload textures into system RAM" option.
Also, if it has not been installed, you will need the AMD dual-core optimizer patch. You can get that from AMD. See the technical support hints and tips post in this forum for more information about that patch.
That video chip is an onboard chip which takes system RAM away in order to do its drawing. It is a very low end video chip, not really meant to run real-time 3D games.