Display problem after upgrade from fc3 to fc4

[fb]

The display was wrong already at graphical 
installation from CD, but after to choose 
"without modprobe" option the display was ok 
again  (in the FC3 there was not any problem 
with the display)  and the upgrade was 
completed.

After the first boot the display become to wrong 
again similar way (double contours and 
mismatching around the cursor). 

When I coming to the KDE and go out and after 
reboot with hard return (instead of normal/soft 
reboot) the display working properly. So 
probably some stupid automatism make the 
problems while the system shutting down. (At 
the normal shutdown the the screen is black 
with green frame instead of the text mode 
shutdown screen.)

 Graphic card is a Matrox G550 (the display 
setting is the same) and the monitor is an Acer 
1711 17" TFT the monitor setting is +Generic 
LCD display 1280x1024" (because that monitor 
type there is no in the KDE display menu)

What can I do?

Thanks in advance:

FB