So let me preface this by saying my system has an rx480 as the main card, and a gtx970 as the compute/vm card.
What I’m wondering tho is if I have the 970 completely installed, but have one grub option for 970 not blacklisted, and one that is blacklisted, could I reboot fast in between tasks and use my 970 for ffmpeg on top of a gaming vm?
Or is there something easier that I could do in-os?
no
grub loads before the os loads during boot to give you the choice of installations.
a vm running on one installation will be shut down when you reboot.
you have the option on switching between installations but only if you are rebooting.
It is posible to use the card on both the host and guest without rebooting.
You may need to kill X first, then you unbind from the nvidia driver, bind to the vfio-pci driver, boot up the VM. When you are done with the VM, shut it down, unbind from vfio-pci, bind to the nvidia driver and restart x. There might be less or more steps, I have not done it myself. You might be able to avoid restarting X by using bumblebee. This might help?
Mell what I meant is like could I have one grub selection be for using the 970 in linux and one for when I want to use the 970 for VM’s. Would that screw anything up?