Ubuntu 7.04 - Failed to start X server

[fear1666]

na početku instalacije mi javi "Failed to start the X Server.
It is likely that it was not set up correctly..."

dalje nakon odabira rezolucije (1680x1050) dobijem "xserver-xorg postinst warning: overwriting possibly-customized configuration file; backup in /etc/X11/xorg.conf.20070529225142"

imam laptop HP 6715b, grafika je ati mobility radeon x1250.

google ne pomaže, pa molim vas da pomognete