setting framebuffer mode during boot

[Gilbert Laycock <gtl1@mcs.le.ac.uk>]

I have framebuffer support compiled into my kernel, and I want to set
the screen mode it uses when I boot. Currently it defaults to a
640x480/80x30 mode, and I want to set it to a higher resolution.

I have an ATI Rage Pro card, so I think I should be using the atyfb
frambuffer module.

According to the Framebuffer HOWTO, and the various readmes in the
kernel source, I should be able to set the framebuffer mode from lilo
like this:

append="video=atyfb:vesa:mode:1152x864-70"

which make difference at all for me. (I have also tried a number of
simple variations, and other modes, but none of them work for me.) 


Another possibility seems to be to use
 vga=<Some VESA mode number> 
in lilo, but I cannot get that to work. Either it will very briefly
switch into the required mode and then switch back to 640x480, or it
will switch into a mode that my monitor cannot deal with and I get a
corrupt screen. Partly the difficulty seems to be to get a definitive
list of VESA mode numbers.


I assume that many people have this working, so what am I doing wrong?

-- 

  Gilbert Laycock                 email:          gtl1@mcs.le.ac.uk
  Maths and Computer Science,     http://www.mcs.le.ac.uk/~glaycock
  University of Leicester         phone:         (+44) 116 252 3902