Here's my config.

GRUB_DEFAULT=0
GRUB_TIMEOUT=1
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on pci_stub.ids=10de:1189,10de:0e0a"
GRUB_CMDLINE_LINUX=""

lspci
01:00.0 VGA compatible controller: NVIDIA Corporation GK104 [GeForce GTX 670] (rev a1)
01:00.1 Audio device: NVIDIA Corporation GK104 HDMI Audio Controller (rev a1)

lspci -n
01:00.0 0300: 10de:1189 (rev a1)
01:00.1 0403: 10de:0e0a (rev a1)

/etc/initramfs-tools/modules
pci_stub

vfio-bind 0000:01:00.0 0000:01:00.1

update-initramfs -u
update-grub2
reboot