In the /etc/inittab file, change the default runlevel from 5 to 3. At this point, you start x-windows with the startx command. But it won't respawn if it fails.
Re-run the graphics setup. The no screens found is usually seen if you haven't found the correct video driver, or all of the video modes for the monitor are invalid.
A log of the startup messages is kept in /var/log/. the log file may have a -0.log ending. It will show which resolution modes it tried.
If you have a problem finding a the correct driver file, you could use the generic 'vesa' driver. Doing this could eliminate the video driver as the problem. If x-windows still doesn't start, look at your monitor model settings for resolution settings.