After searching google and this forum without success, I decided to comment on the case:

On a Toshiba laptop with Intel graphics, the system I started in text mode and asks me login. First user entered, then step to "su" and then shutdown-r now, and the third (more or less) usually start in graphical mode.

If after booting into text I write startx starts smoothly (in KDE 3.5)

There is only one user with autostart.

Another thing:

KDE 4.2 is marked Kmix "silence." Ok uncheck it and everything, but the next reboot still marked silence.

Thanks for your time