Thanks for replying Brian.

>Since running X without an XF86Config file is working, try the
>following command to generate your XF86Config:
>
>     # X -configure
>
>This probes and generates a corresponding XF86Config file.  You
>need to run this as root.  The XF86Config is generated in your
>current directory, IIRC.

'X -configure' created the file /root/XF86Config.new.  When I moved 
it to /etc/X11/XF86Config and executed startx the result was a 
totally black screen.

I noticed 'X -configure' had selected the i810 driver and thought I'd 
try using the vesa one instead (something I should have done 
yesterday) and it worked.  I made that change to my previous 
XF86Config and put "1280x800" as the first resolution on the 
'Subsection "Display"'s Modes line, which produced a resolution close 
to what I wanted. :)  kde's desktop configuration dialog box says 
it's 1024x768 and doesn't give 1280x800 as an option for some reason.

I'd assumed a generic driver wouldn't perform very well compared to 
the i810, but kde is quite responsive with the vesa driver.  Perhaps 
someone will discover the reason for the 'agp0 at pchb0: unknown 
memory configuration, disabling' message during booting sometime.


Ray