>What brand monitor do you have?
>Sometimes the monitor can not handle svga (3d and high
>color graphics). CLIM works as it should though. So
>maybe it is the monitor that's at fault.
>Maybe you can search for your monitors compatibility
>with XFree86 on the internet.

If your monitor has been working fine upto now, it's probably not the 
monitor per say.  It would be helpful to know what you set your XF86Config 
file for, especially the "monitor", "device" and "screen" sections.  Is your 
machine a Notebook?  What graphics chip does the machine have?  What's the 
capabilities of your monitor?

If your config file is setup for the correct monitor and graphics chip, then 
maybe you're trying to use your monitor in a mode it cannot handle - e.g. 
1280x1024 resolution but your monitor can only go upto 1024x768.

Robert