Nvidia GeForce 1050 Ti Only single display after upgrade from 6.9.2 to 6.12.4

[yardon1]

I've been using the old 6.9.2 version for the last few years with no issues. Decided to upgrade to 6.12.4 and I can no longer use my second monitor in a Win10 vm.  Attempting to enable the second screen and I get the message 'This card only supports a single monitor'

 

Downgrade to 6.9.2 and it works fine again - albeit I have to re-enable the second monitor in software.

 

My OpenSuse VM still works perfectly with dual monitors under 6.12.4.

 

I created a new Win11 VM to check, and this has the same issue. I installed the latest driver from Nvidia and this made no difference

 

One monitor is connected via display port whilst the second is via DVI. The DVI connected one does not show

One other thing I have noticed. I have an autostarting Ubuntu vm that runs a CUPS server. This fails to autostart  with a vfio error, but runs fine when I start it manually. This does not have any passthrough set other than the processor

 

Any pointers would be appreciated.

[yardon1]

Made some progress with this. Looks like there are two issues which need to be addressed at the same time

 

Firstly the sound card part of the Nvidia card needs to be passed through (I didn't have to do that with 6.9.2)

Secondly my Asus Xonar pci  sound card cannot be passed through. If I leave it in, the whilst passing through the Nvidia sound, the vm fails to boot

 

Doing both of the above then allows both monitors to work.

 

I'll investigate further as I'd like to have sound on the win vm. (I use optical output from the card to connect to an old amp and stereo speakers). My guess is it's something to do with the i440fx machine type or the BIOS as there are no such issues with Tumbleweed