Display output is not active (Chrome OS Flex)


New Member
Mar 3, 2022
Good Afternoon,

I am trying to install Chrome OS Flex in a VM on Proxmox 7.1-10.

As soon as it boots into the installer my console screen goes black and this message is displayed "Display output is not active".
Does anyone know how I can resolve this issue?

Many thanks.

VM details:
Processor 4 Cores (host)
Display Virtio GPU
Machine q35
Hard Disk SATA 17GB SSD
USB0 Host pass through (installation media)
did you try different display types? (vga/spice/etc.) ?
Thank you @dcsapak . I have tried, but it only boots with VirtIO-GPU. I have assigned it maximum allowed memory of 512MB. The rest are causing the VM to constantly reboot/loop or crash.
I too have noticed this, hence the search. Seem to affect both my win and linux VMs. Have to kill the VM and restart. Still searching, fingers crossed..

In one of my cases (Ubuntu server 20.04.4) its listed as;

00:02.0 VGA compatible controller: Red Hat, Inc. Virtio GPU (rev 01)
Last edited:
This is my VM, and it's working almost perfectly.
The video update that is not good.

Have a nice day.


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have you also tried to give it less video memory (e.g. leave it at default) ? for some options (e.g. spice), it's not good to give 'too much' vram
for me it works best with the VirGL GPU option. the Virtio-GPU however has refresh issues. with VirGL everything is smooth (running with 32 MB vram)
Is it possible to run "Linux development environment"? When I try to turn it on - it fails to create virtual machine. I use CPU = host and nested virtualization is enabled.
Hello everyone,

I am currently having the same problem.

Chrome OS Flex is very slow and image crashes after a while. Has anyone now found a setting with which it runs smoothly?

With VirGL GPU it doesn't start at all for me...
Same problem here, except that I 'm not using VirGL GPU, I 'm using VirIO-GPU and I tried from 256 to 512, and then down to 48 MB, that is best when is running, however as soon as it goes to sleep mode, screen never come back, and as all around I got screen is not connected. Then the machine reboots itself


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