Ask Ubuntu is a question and answer site for Ubuntu users and developers. It's 100% free.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have installed Ubuntu 12.04 on the latest VirtualBox release and I cannot change the resolution.

Here are the commands that i run:

-- in Windows

VBoxManage setextradata "Ubuntu" "CustomVideoMode1" "1920x1080x32"

-- in Ubuntu

~$ gtf 1920 1080 32 

# 1920x1080 @ 32.00 Hz (GTF) hsync: 35.20 kHz; pclk: 86.17 MHz
  Modeline "1920x1080_32.00"  86.17  1920 1992 2184 2448  1080 1081 1084 1100  -HSync +Vsync

~$ xrandr --newmode "1920x1080_32.00"  86.17  1920 1992 2184 2448  1080 1081 1084 1100  -HSync +Vsync
xrandr: Failed to get size of gamma for output default

Because this fails, xrandr --addmode does not work either. I kept searching the webs and there's a common reccurent theme with a file /etc/X11/ but this is apparently missing from my image.

Also the scroll doesn't work.

share|improve this question
Did you install Guest Additions correctly? See also:… – Takkat Feb 10 '13 at 18:15
Takkat is quite correct. Once installed, you can resize the guest like any other window, negating the need for any complex mode switching. – IlluminAce Mar 3 '13 at 19:18

I found that for this VM screen-resizing to work properly on Ubuntu 12.04 guest VMs, you need to have a fairly recent version of the VirtualBox guest additions. It is not enough to use the version of VirtualBox distributed in the Ubuntu package repostories. I think that you can use VBoxGuestAdditions 4.1.24 and it will work with Ubuntu 12.04 guests. You need to install the 'dkms' package, possibly also 'kernel-headers', and after that the guest additions 4.1.24 can be installed from the .iso

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.