onboard trident video drivers

Hi 
 
Im trying to get XFree86 going on a system I have. The board is from
www.dfi.com <http://www.dfi.com/>  (not very helpful people) and it's a
CM33-TC. 
 
It has an integrated graphics chip which DFI lists as a "Integrated
Trident 2D/3D/Video accelerator". 
 
I cant establish which driver to select when im configuring the
layout??? I've tried a couple of trident drivers- but I just get a
garbled screen when I start the X window system and the system just
hangs, I cant even do a Ctrl Alt Bkspace.
 
Can anyone help?
 
Many thanks