I tried to reinstall using safe graphics mode and it worked perfectly. So it may be an issue with Matrox G550 card...
On the other hand I forgot to format /usr -partition from my previous fedora 4 -install before installing kubuntu on my first attempt so that could have played a role also... -- Installer crash on kubuntu 6.0.6 https://launchpad.net/bugs/50560 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs