Problem with ATI M3 and xfree86

Hello,

Perhaps you can help me with   my problem? I try to activate the 
external monitor (a Beamer 1024X768) within my SuSe Linux 8.1 while 
running 1400x1050 on my laptop internal LCD. My SAX configurator does 
not allow me more than the internal screen on my ATI. If I virtually 
insert a second ATI, the X-server complies about missing drivers and 
fonts. I mean I configured the driver as if I had a second card, because 
this also allowed me to configure a second screen. But this was probably 
a misunderstanding of the driver docs.
To be clear: what can I exactly do to generally use 1400x1050 internally 
and to switch "with a fingertip" to 1024x768 for presentation on the 
external screen? I can live with it if the internal LCD switches off 
during presentation.
Under Windows 2k the ATI drivers can handle the two different 
resolutions internally and externally. The driver says I have a ATI 
mobility M3 in my Thinkpad A20p.

Is there a solution?

Regards
     Reinhard Moeller
[email protected]