thanks for the hints - here is the verbose logfile
I had to change the settings as you suggested to make the crt become active and having both displays - but it looks horrible on the crt -
on the console (vga=794) even with bootsplash the crt runs with an excellent resolution and refreshrate. It almost displays in better quality than the dfp on the laptop.
We'll have to get some beers if we make my system run again nicely