I am trying to passthrough my Nvidia NVS 5200M on my Thinkpad T430s. I am having some trouble with the infamous ERROR 43. Interestingly sometimes on frist boot of the vm, the GPU passthrough works without a problem. I then tried to boot native windows from a flash drive and use GPU-Z to dump the vBIOS, however I get an error saying the GPU does not support vBIOS dumping. I then proceded to try and boot it into a ubuntu vm and the nouveau driver failed to load: 
My settings/setup:
-BIOS (tried both BIOS and UEFI)
-i440fx chipset (also tried q35 with no success)
-no additional flags to hide the hypervisor since this is a professional GPU and should support virtualisation without hiding it (I also tried setting the qemu flags, and setting kvm hide state to an but it changed nothing)
Is there anything I can do?