Disabling hardware acceleration for 3D apps.

[kumar vemuri]

Hi,

 I have the 3D graphics driver installed on my linux system. 

a. How do i disable hardware acceleration and make a 3D game use the
libGLCore (s/w renderer) of Xserver (without uninstalling the driver)? 

b. Are there 3D apps/games which start/work (however slow) if h/w
acceleration is disabled?

Thanks
K