I have two Notebooks, a Dell Latitude D600 and a Compaq Evo N160. On both systems I have installed Knoppix on the hard disk (Dell with Knoppix 3.6 and Compaq with Knoppix 3.4) as a Debian system. Both systems work fine, but when I try to make a presentation with our Beamer, the Beamer shows (independent of the notebook) just the middle part of the screen.

The reason seems to be, that the beamer gives DDC no signal about the resolution as I can see in the log-file of XFREE. As a result XFREE works in clone mode with a lower frequency (about 31.5 Mhz) on the beamer. When I start the notebooks connected with an external monitor who gives information about his resolution and afterwards swap the VGA cable with the one of the beamer everything works fine. Is there any chance to fix this problem in the X-configuration, so that I can connect to the beamer without going to clone mode?