Ubuntu 7.10 says no screens found after typing sudo X
 

I try to boot up my system and when i click start/install ubuntu it loads a text based interface. when I type sudo gdm it says its already running. I tried to do sudo X but it stopped working and my moniter says the resolution is out of range. my max resolution is 1240x1040 (or 1280x1080) and I always use that. Could someone help me get it to boot into the GUI?
I did sudo dpkg-reconfigure xserver-xorg and after it finished it brought me back to the command line. I then typed sudu X and then an error came up saying no screens found. Help?

a) you should not start X with sudo X. Use gdm or run the startx script as a normal user instead.

b) please provide us some information about your system
- graphics card (lspci)
- /etc/X11/xorg.conf
- /var/log/Xorg.0.log

c) I have never seen a monitor with those resolutions. If you are sure these resolutions are correct, you will need to add a modeline to your xorg.conf.