The /etc/X11/XF86Config file tells the X server what kind of
monitor,
video card and mouse you have. You must create it to tell the
server what specific hardware you have.
You'll need info on your hardware:
The recommended way to generate an XF86Config file is to use the
xf86cfg utility. The xf86config text utility is still there
for the (few) cases where xf86cfg can't be used. Also, there is a
sample file installed as /usr/X11R6/lib/X11/XF86Config.eg,
which can be used as a starting point.
For details about the XF86Config file format, refer to the
XF86Config(5) manual page.
Once you've set up a XF86Config file, you can fine tune the video
modes with the xvidtune utility.
XFree86 4.3.0 has support for the mouse driver included in
the wscons console driver introduced by NetBSD 1.4. Specify
``wsmouse'' as the protocol and ``/dev/wsmouse0'' as the
device in /etc/X11/XF86Config if you're using NetBSD 1.4 or later
with a PS/2 mouse.
For older releases, the NetBSD pms mouse driver handles PS/2 style
mice as Busmouse. Specify the protocol as ``busmouse'' in the
mouse section of your XF86Config file if you're using a PS/2
mouse with NetBSD 1.3 or former releases.
Only standard PS/2 mice are supported by this driver. Newest PS/2 mice that send more than three bytes at a time (especially Intellimouse, or MouseMan+ with a wheel) are not supported by NetBSD 1.3 and former releases.
See README.mouse for general instruction on mouse configuration in XFree86.