seabios vs omvf

[luca2]

Hi,

Wanted to ask if there is any performance gain of using omvf instead of seabios in a win10 vm (with AMD r9-290 passthrough).

I am having issues to create this vm with omvf (on the other hand I have no issues with seabios).

Rgds.

[alexciurea]

hi

not able to tell all the differences, other than seabios is suitable for passing through non-uefi devices, while ovmf is recommended for uefi ones.

to my understanding, seabios is more stable but has less features than ovmf.

 

i also noticed that success depends on the os you are trying to install (some linux distros worked for me only with seabios, while others only with ovmf, although i was passing through same GPU)

(on a new generation mobo)

 

[testdasi]

VNC on OVMF limits the resolution, at least on my Win10 VM. And some Linux distro mess up the efi partition so unbootable under uefi.

You might have to try to see for yourself, unfortunately. The one that works is the better one.

[billington.mark]

Seabios works great with non UEFI graphics cards passed through and when you don't need to boot from anything other than a VIRTIO controller (anything where 'bus=virtio' in your XML for the disk you're booting from)

 

OVMF comes into its own when you want to boot from passed through devices like a SATA controllers or PCI-e NVME devices. You can still pass these through with Seabios, but you'll not be able to use them as a boot device.

 

Performance wise, if you can boot from either with your VM setup, there's no difference.

[luca2]

Thx all for help!