virtualbox.org

Firstly, apologies if this has already been posted or recognised elsewhere - so far I've not been able to find anything with the same issue.

Host Specifications:
MacOS 10.4.4
VirtualBox 6.0.6

Guest Specifications:
Windows 10 (1803)
Build: 17134.706

I was previously running VirtualBox 5 which was fine (although sometimes my Windows 10 VM would get stuck at a black screen and I'd have to power cycle it). I then updated to VirtualBox 6.0.6 which has now caused the Windows 10 VM to incorrectly auto-scale. The screen flickers between being the correct dimensions/scale to being too large. Turning off 3D acceleration appears to fix this issue but this is not ideal as now the VM is very slow.

I just wondered if others are experiencing the same problem? Any help would be much appreciated!

Charles

charlesomer wrote:has now caused the Windows 10 VM to incorrectly auto-scale

What does that mean?

Shut down the VM. Go to the VirtualBox Preferences » Display » Scale Factor : set it to 200%. Restart the VM...

If that doesn't fix it, we need to see a complete VBox.log, from a complete VM run, where the problem occurs:

• Start the VM from cold-boot (not from a paused or saved state) / Observe problem / Shutdown the VM (force close it if you have to).
• With the VM completely shut down (not paused or saved), right-click on the VM in the VirtualBox Manager and select "Show Log".
• Save only the first "VBox.log", ZIP it and attach it to your response. See the "Upload attachment" tab below the reply form.

I would also like to see the "recipe" of the VM, the ".vbox" file:

1. Right-click on the VM in the VirtualBox Manager. Select "Show in Finder/Explorer/Whatever".
2. ZIP the selected ".vbox" file and attach it to your response.

Wow setting it to 200% fixed the issue! Thank you!

What's the reason for this?

charlesomer wrote:What's the reason for this?

Improved support for the HiDPI displays. Your Mac is able to run 10.14, so I assumed that it's the HiDPI kind (Retina). HiDPI ones work better if the "perceived" size of the VMs gets doubled. You can also see the wording if you click on the status bar of a windowed VM on the Display icon (): Virtual Screen 1: 100% (unscaled output), 200% (autoscaled output).

BTW, that's what OSX does as well. My MacBookPro11,5 has a "marketing" label of 2880x1800, but even on the highest setting in the Displays » Display setting (More Space) it lists it as "Looks like 1920x1200"...

One thing to remember; avoid like the plague setting the ScaleFactor for an individual VM. Once set on a VM, then that ScaleFactor for the VM is "permanent" and doesn't follow the global Preference ScaleFactor. If you want to reset it you have to manually go for the command:

• 
  VBoxManage setextradata "<VMname>" "GUI/ScaleFactor"

Excellent! Thank you, that makes sense!

I tried changing the scale, toggling 3d acceleration, and even limiting the resolution on the host for the problem monitor, but still have an autosize issue. On the bright side, I've now learned how to pull up Force Quit with a key command, which I never needed before.

System:
new Mac Mini running 10.14
Both VB 5.28 and 6.0x have the same issue
Windows 10 Guest, trying to be run on two of my three monitors
two monitors are 24" and third (the one giving me a problem) is 27" - all with max resolution of 1920x1080

What could help my issue is limiting the guest vm to the correct two of the 3 monitors, but I can't seem to get the monitor selection process straight. Which monitor is 1, 2 or 3?

In the meantime, probably from all the force restarts of the guest, I am having trouble getting it open at all, but will work on only using two monitors. Thanks for anyone's help.

(Also, I did attach a log, but don't know if it is helpful or not)