VirtualBox Monitor Resolutions with XP Host, BSD Client and xfce [closed]

Question

I'm running VirtualBox on an XP host and I have installed FreeBSD 7.2 using xfce as my window manager. Everything works fine except for the monitor resolution. I can only access the old standard ones: 640 x 480 -- 1600 x 1200. The problem is I'd like to run VirtualBox as full screen on a 1680 x 1050 res monitor. I've tried the following

1. VirtualManage.exe setextradata BSD7.2-Mk2 GUI/MaxGuestResolution 1680x1050x24 (along with several other variants in resolution and bit-depth.
2. Editing /etc/X11/xorg.conf under the Screen section with Modes "1680x1050" (along with variants).

I can't seem to make this work and I can't tell whether it is a limitation in VirtualBox, FreeBSD, X, xfce or a combination.

Answer 1

Have you tried installing Guest Additions? From your VM, mount the ISO and run the script that corresponds to your OS.

Answer 2

I have the wrong VirtualBox command line expression. Running the following in a terminal:

VirtualManage.exe setextradata BSD7.2-Mk2 CustomVideoMode1 1680x1050x16

and then making the appropriate entries in xorg.conf works. Unfortunately, it only works in 16-bit mode; 24-bit doesn't work.