Select video output for Proxmox

[vaschthestampede]

Hello everyone!
I'm new so I hope I don't make the typical trivial mistakes of newbies.

I have multiple graphic cards mounted and would like to decide which proxmox comes out with by default.
The best thing actually would be to disable the graphics output altogether so that you can dedicate all possible cards to passthrough.

Feel free to ask me what other information may be useful.

 

[AKA]

Mostly this is a BIOS/UEFI Setting. If not, mostly the GPU in the first slot is used as default output.
If you can figure out, which output it is, you can make it available for passthrough anyway by setting the following grub parameter:
GRUB_CMDLINE_LINUX_DEFAULT="_OTHER PARAMETERS_ video=efifb:off"
However, this makes the first slot GPU available for Passthrough, even if proxmox puts out there.

You can find more information here: https://passthroughpo.st/explaining-csm-efifboff-setting-boot-gpu-manually/

 

[vaschthestampede]

I tried to follow yor advice.

This is my grub file:


But I get this on the VM:

 

[AKA]

Okay, but what's the exact error?

I'm really unable to understand with only a screenshot from the device-manager, sorry.
The fact, that you can forward it and the VM doesn't crash or does not start is a good sign though.

 

[vaschthestampede]

I try to explain better.

The problem is that the operating system, while seeing the presence of the video card, does not use it for graphics acceleration.
The other system (using another card) sees it perfectly.

I tried swapping cards but nothing.

Did I correctly follow your instructions for editing the grub file?

 

[AKA]

Okay, i guess i got it.

I'm not an expert in this.
I just now a couple tweaks and issues that can occur while PCIe forwarding.
Did you check your BIOS/UEFI if there is any chance to have an option to which GPU is primary output?

 

[vaschthestampede]

I made this change:


Now it works.