xorg.conf file: renamed old one, but no new one formed

[H.S.]

Hello,

I connected a new monitor to a machine running Hardy. Since the newer
resolutions were not being shown in System->Preferences->ScreenRes., I
renamed xorg.conf (in /etc/X11) to xorg.conf-bk having read that this
would force recreation of the file upon next gdm restart (or reboot).

Upon rebooting the machine, no new xorg.conf was formed. However, from
my system->preferences->screen resolution I could see that the new
monitor had been detected successfully and I was able to use the new
full resolution.

But I still do not have any xorg.conf in /etc/X11. What gives? I thought
this was a necessary file. I am not sure I understand this properly. Any
explanations?

Thanks.
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