My card, a Diamond Stealth 64, needs the XF86_S3 driver; XFree86 4 doesn't
seem to support it. /etc/X11/XF86Config is correctly configured, but
/usr/X11R6/bin/X -> XFree86. I couldn't find Xwrapper, so I made it a
symlink to XF86_S3. It could find the config file, so I symlinked
/etc/X11/XF86Config to /etc/XF86Config. Now it works.
Please reopen if this persists in beta4 or later.