I have VirtualBox instance of Centos 5. The screen size is quite small (800*600) and I'd like to increase it to 1280*1080. Under the Gnome preferences for "Screen Resolution" I only get the option for 600*800 or 640*480.
I've tried editing my xorg.conf (based on this tutorial http://paulsiu.wordpress.com/2008/09/08/creating-and-managing-centos-virtual-machine-under-virtualbox/) but it doesn't seem to have made a difference. Here is a snippet from the edited section:
Section "Screen"
Identifier "Screen0"
Device "Card0"
Monitor "Monitor0"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Depth 24
Modes "1280x800"
EndSubSection
EndSection
Does anyone know how to do this?
Best Answer
A maximum resolution of 800x600 suggests that your X server inside the virtual machine is using the SVGA driver. SVGA is the highest resolution for which there is standard support; beyond that, you need a driver.
VirtualBox emulates a graphics adapter that is specific to VirtualBox, it does not emulate a previously existing hardware component like most other subsystems. The guest additions include a driver for that adapter. Insert the guest additions CD from the VirtualBox device menu, then run the installation program. Log out, restart the X server (send
Ctrl+Alt+Backspace
from the VirtualBox menu), and you should have a screen resolution that matches your VirtualBox window. If you find that you still need manual tweaking of yourxorg.conf
, the manual has some pointers.There's a limit to how high you can get, due to the amount of memory you've allocated to the graphics adapter in the VirtualBox configuration. 8MB will give you up to 1600x1200 in 32 colors. Going beyond that is mostly useful if you use 3D.