I'm using xfce 4.4.1 on a Dell laptop Inspiron 6000 having Intel 915GL chipset for the graphical card and was unable to get resolution size of 1920x1200 pixels. xdpyinfo command return correct size and startx also return correct size. Only startxfce4 doesn't work with this size or lower. I'm also using 915resolution program to set the resolution at boot time and it's work so I presume that the problem come form XFCE. which program is responsible for the screen resolution in XFCE? and do you have an idea about what XFCE cannot correctly detect xorg.conf setting?
The resolution is set by your xorg.conf file. If it's not set properly, xfce will do no magic.
Xorg is able to determine what resolution to use based on the DCC data from the monitor, and matches that with the resolutions supported by the video card.
Please direct you call to the Xorg mailing list:
Xfce itself doesn's set the X resolution.
There is a plugin (the so called "Display plugin") that uses the XRandr extension to allow the user to change the resolution on the fly, but this relies on Xorg to be able to list the valid resolutions.
A simple "xrandr -q" will list the modes that Xorg is able to detect on your system.
Thanks for the clarification, I'll contact Xorg to inform them about my issue. I think we can closed this ticket.
Close bugs in products that are not active anymore.