Can only start X with second monitor attached
 

Since a couple weeks ago, I find it impossible to start my X without using a second monitor.

Already removed /etc/X11/xorg.conf, did xorgsetup, X -configure, but nothing seems to solve this issue.

There are no errors in /var/log/messages or /var/log/Xorg.0.log

Sometimes, when I run the command startx, the hostname is lost, and I have to issue again `hostname localhost`.
In the past, a couple of times, I loaded X after `xwmconfig` and choosing another window manager. But already tried all of them and X, or perhaps the window managers cannot keep connected to X.

After `startx`, X starts, the window manager starts, but after some seconds, the window manager closes and all I have is a black screen with an underscore at the top left corner.
All I can do at that time is to ctrl + alt + backspace and return to text console.

Don't know what else to do. I'd appreciate any help on this problem.

you may try xinit: http://www.xfree86.org/4.2.0/xinit.1.html

Anything in ~/.xsession-errors?