HOST MACHINE: Macbook Air 2017
GRAPHICS: Intel HD Graphics 6000 1536 MB
MACOS: Big Sur 11.2.3 and later
VIRTUAL BOX Version 6.1.19 and later
Intel HD Graphics 6000:
Type: GPU
Bus: Built-In
VRAM (Dynamic, Max): 1536 MB
Vendor: Intel
Device ID: 0x1626
Revision ID: 0x0009
Metal Family: Supported, Metal GPUFamily macOS 1

  1. On my primary display, every VM runs very well. But as soon as I move the window on the secondary display, every VM becomes very slow and unresponsive sometimes.

  2. If I unscale the resolution of the VM, let's say I set 800x600 => the VM becomes responsive even on the secondary monitor.

  3. If I close the laptop lid and use the second monitor as the primary display, I can use the VM with no problem even at maximum resolution (in my case is 1920x1080x32 @0.0)

  4. I tried different software to emulate VMs and the problem seems to be correlated to VBox only.

MOST IMPORTANT 5) If I go to Display settings -> Arrangement and switch the menu bar to the other display, the second display becomes responsive and the primary becomes laggy.

What could be the problem and possible solutions?

I tried to unscale the resolution, use different settings for the VM (different video adapter, memory size, processors...) but with no success. Furthermore, I also tried to monitor the CPU, GPU, memory usage both on the host and the guest machines and nothing appears to be abnormal. I tried all the possible VirtualBox version macOS Big Sur compatible and even software to use the iPad as a secondary display and the situation is the same.

Please, any help would be very appreciated!

  • So, if you don't run VirtualBox, the problem goes away? I think that's the focus of the problem. – benwiggy Apr 14 at 14:50
  • After several test, I can confirm that the problem is strictly related to VBox – aletullio Apr 16 at 12:13
  • 1
    Can you specify the adapter or method used to connect the external display? For example, on a Macbook Pro running an adapter that supports Displaylink or USB C, it uses software based video to the external display rather than hardware supported, which a thunderbolt one would have. – akostar May 3 at 7:07
  • I normally use minidisplay port (thunderbolt) to HDMI video adapter. I've tried also thunderbolt to VGA or using the iPad as an external monitor through software -Yam Display in my case- and the results are the same. – aletullio May 3 at 13:02

You must log in to answer this question.

Browse other questions tagged .