How to enable dynamic display resizing with Windows 10 guest?

I’m new to QEMU and I created a Windows 10 VM on a laptop running on Kubuntu 20.10.

How can I enable dynamic display on it? When I selected View → Scale Display at the menu bar, nothing popped up.

If you want to resize the resolution of your Windows guest when using a Spice display you need the Spice Guest Tools for Windows installed in your guest.

That’s done already.

Can you check in Windows if you can select different resolutions? What happens when you select a higher resolution?

The resolution changes, but doesn’t auto-adjust.

View → Resize to VM

For some reason, the submenu doesn’t show up.

Are you clicking on View in the virt-manager window or in the window of your virtual machine? Can you maybe post a screenshot, I have no idea what you are doing.

Fixed it. I had to change the Graphical Console Scaling to “Always” instead of just “Fullscreen”.

Thanks so much!

Another question: any idea how to improve the performance? I’m planning on doing a GPU passthrough with my next gaming PC, but right now, I’m doing it on my laptop (current gaming PC is only a 6th gen i5).

You need to make sure your next motherboard has good IOMMU groups where the devices are separated well. I have heard these days many motherboards have good support but buying a board that people have tested thoroughly and is known to work is what I have done.

The Arch wiki is a good place to start but there exist also guides for other distributions. Currently one for Fedora was a work in progress here on the forum if I am not mistaken.

if your running virtual box. install the extensions via the vbox tools menu.

Oracle VM VirtualBox Extension Pack. it should allow you to adjust your display settings.

Sorry for late reply, but aren’t they separated by default? What makes a motherboard have bad IOMMU groups?

In that case, you can try using a kernel with the ACS patch.