I have tried all alternatives and resources that I found on internet to achieve to change screen resolution in my MacOS X guest. I have the latest VirtualBox version (4.1.22) and I have MacOS X 10.6.3 Snow Leopard running in a vm guest.

Some solutions that don't work for me are:

  • Tuning virtual machine settings:

Adding and in the .vbox file, or running these two commands:

vboxmanage setextradata "MAC OS X" "CustomVideoMode1" "1360x768x32"
vboxmanage setextradata "MAC OS X" "GUI/CustomVideoMode1" "1360x768x32"
  • Editing Guest OS boot configuration:

Modify /Library/Preferences/SystemConfiguration/com.apple.boot.plist with these lines:

<key>Kernel Flags</key>
<string>"Graphics Mode"="1360x768x32"</string>
<key>Graphics Mode</key>

Any other suggestion, something that I was missing.

Thanks in advance,

  • have you installed the Guest Additions?
    – JoshP
    Sep 24, 2012 at 20:52
  • 2
    Until now, there are no Guest Additions for MacOS Guest.
    – Pymoo
    Sep 25, 2012 at 8:58

4 Answers 4


I am using VirtualBox under Ubuntu Linux, and a Mac OSX (Mountain Lion) as guest OS.

For me, the full resolution started working when I did all of the following:

0) Install MultiBeast 4, making sure that the system boots from the virtual hard disk rather than from any booting CD. I followed the instructions here:


However, at the end of the procedure I did not have the full resolution, which for me must be 1920x1080x32.

1) In the virtual machine, edit these PLIST files,

sudo pico /Extra/com.apple.boot.plist/Library/Preferences/SystemConfiguration/com.apple.Boot.plist

In this file, inside <dict>...</dict>, insert:

<key>Graphics Mode</key>
<key>Kernel Flags</key>
<string>"Graphics Mode"="1920x1080x32"</string>

sudo pico /Extra/com.chameleon.Boot.plist

In this file, inside <dict>...</dict>, insert:

<key>Graphics Mode</key>
<key>Kernel Flags</key>
<string>npci=0x3000 darkwake=0 "Graphics Mode"="1920x1080x32"</string>

I noticed that I already had some "kernel flags", so I just added another one for "Graphics Mode". Also note that "Graphics Mode" has a space inside it.

2) Shutdown the virtual machine and do the commands

vboxmanage setextradata "MAC OS X" "CustomVideoMode1" "1360x768x32"
vboxmanage setextradata "MAC OS X" "GUI/CustomVideoMode1" "1360x768x32
VBoxManage setextradata MountLion VBoxInternal2/EfiGopMode 3

After this, the virtual machine boots with full resolution.

Now, this might be overkill, and the result could be achieved perhaps with fewer options, but I tried various things until it started working.

  • 3
    Thanks, it looks like this could be overkill. I got it working in far fewer steps: Just altered the "1920x1080x32" string to my resolution in /Extra/com.chameleon.Boot.plist and added the CustomVideo1 setting to the vbox file for the VM. Mar 11, 2013 at 15:23
  • 2
    Thanks for the answer; I altered each of the settings noted above one at a time, and it didn't work until I got to the vboxmanage settings. However, I set CustomVideoMode1 and GUI/CustomVideoMode1 to 1920x1080x32, and EfiGopMode to 5 (someone on another forum mentioned that being correct, yet undocumented, for 1920x1080). Of course, I sub'd my own machine name in the commands. What I didn't understand, and didn't try, were the 1360x768 values if you're going for 1920x1080.
    – s.co.tt
    Nov 1, 2013 at 19:22
  • setting EfiGopMode is the only step necessary here
    – gordy
    Apr 23, 2015 at 5:05
  • 1
    Tried the same for Mavericks and did not work :(
    – Mukus
    Aug 8, 2015 at 9:26
  • 4
    The new way is VBoxManage setextradata "VM name" VBoxInternal2/EfiGraphicsResolution HxV, as specified here and here. (I can't create an answer for lack of reputation)
    – B3ret
    Feb 20, 2018 at 12:08
VBoxManage setextradata "mac" "VBoxInternal2/EfiGraphicsResolution" "1920x1080"

did the trick for me on high sierra

  • 3
    only this worked for me. Nov 7, 2017 at 13:41
  • @TamásBarta are you working on high sierra too?
    – cyptus
    Nov 7, 2017 at 13:53
  • 1
    yes, from Arch Linux host Nov 7, 2017 at 14:00
  • Didin't work for me on Ubuntu 17
    – Chlebta
    Dec 5, 2017 at 11:13
  • Worked for me; High Sierra, Arch host, 2560x1080 res. Dec 23, 2017 at 8:08

For the record, I found this advice that allowed me to change the resolution:

VBoxManage setextradata "vmname" VBoxInternal2/EfiGopMode 3

where the last param is one of:

0 – 640×480
1 – 800×600
2 – 1024×768
3 – 1280×1024
4 – 1440×900
5 – 1920×1200 

I'm running VBox 5.0.14 on OSX 10.9 (host), and the guest is OSX 10.11.

  • 4
    Are there higher resolutions using these numbered settings?
    – user225451
    Aug 27, 2016 at 0:41
  • This works for the fixed resolutions available in the list. 1440×900 worked for me as it was same as my host resolution and i could move the guest to full screen and it was neat!
    – Vikram Rao
    Mar 10, 2017 at 11:50
  • I have fedora 25 as host, and OSX sierra as guest (from vagrant box). This method worked for me, thanks a lot! Apr 20, 2017 at 9:25
  • This worked for me, with doing nothing else and setting nothing else. Also, do yourselves a favor and take a snapshot before.
    – kontur
    Jan 13, 2018 at 12:02

I followed @winitzki and these are the steps I did.

I want to set the resolution to 1920x1080, change yours accordingly.

Backup files before editing.

  1. sudo vi /Extra/com.chameleon.Boot.plist

Add the following inside <dict></dict>

<key>Graphics Mode</key>

Update the value for Kernel Flags key with

"Graphics Mode"="1920x1080x32"

Final should have the following 4 lines (note some extra data in Kernel Flags, keep them as is):

<key>Graphics Mode</key>
<key>Kernel Flags</key>
<string>npci=0x3000 "Graphics Mode"="1920x1080x32"</string>
  1. Shutdown VM.

  2. Update VirtualBox config.

My VM Name is "MAC".

vboxmanage setextradata "MAC" CustomVideoMode1 1920x1080x32
vboxmanage setextradata "MAC" "GUI/CustomVideoMode1" 1920x1080x32
vboxmanage setextradata "MAC" VBoxInternal2/EfiGopMode 5
  • On macOS 'El Capitan' in VBox 5.1 it is enough only last 3 strings about setextrasettings.
    – kyb
    Oct 3, 2017 at 13:22

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