I’m a machine learning researcher running Ubuntu 20 on a 3950X with dual GPUs: a low power 1650 and a 2070Super (for pass-through). I’ve tried every browser and every setting in Firefox to get video playback acceleration working with no success.
The 2070 Super is detached from the nvidia driver and is assigned to kvm (vfio). Every time I start Firefox (or any other browser, including Chrome) I get the error:
[GFX1-]: More than 1 GPU from same vendor detected via PCI, cannot deduce device
Last time I checked, nVidia VAAPI support (blob driver) is not great and it favours VDPAU, which is not supported by Firefox. As a result, all decoding in Firefox (e.g., YouTube) runs on my CPU.
Any ideas on getting hardware accelerated video decoding working in Firefox in a multi-GPU nVidia setting?