
By default, OpenBSD 4.6 doesn't ship with an nf file, just using the default config. Next, boot OpenBSD or FreeBSD in the VM and use the block of text below as your /etc/X11/nf file. VBoxManage setextradata CustomVideoMode1 In my case, my MacBook's native resolution is 1280x800 and I really don't mind running X.org at 16bpp for a guest OS. Use the VBoxManage utility on the host platform (VBoxManage.exe on Windows, VBoxManage on Linux, /Applications/VirtualBox.app/Contents/MacOS/VBoxManage on OS X) and do the following where is the name of the VM and is the resolution and bit-per-pixel you're running your host OS at, such as 1280x800x16. First, I had to set a custom video mode in VirtualBox. To get OpenBSD's guest to run X at full-tilt, I had to do some hacking and tinkering. When you start playing with some of the more obscure OSes, though, there's no guest additions. It allows you to resize the window and get an instant resolution change to go along with it. One thing I love about VirtualBox is the Guest Additions package, for Windows and Linux guests.
