Settings different GPU as default display in multi GPU ubuntu

Question

Used previously posted threads from this forum to set up my 1030 card as the display card done the following steps:

lspci | grep VGA

17:00.0 VGA compatible controller: NVIDIA Corporation Device 1e04 (rev a1)
65:00.0 VGA compatible controller: NVIDIA Corporation Device 1e04 (rev a1)
b3:00.0 VGA compatible controller: NVIDIA Corporation GP108 [GeForce GT 1030] (rev a1)

then in

/etc/X11/xorg.conf
changed to 
Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    BusID              "PCI:b3:0:0"
    VendorName     "NVIDIA Corporation"
EndSection

connected the HDMI cable to the card, restarted, and got no display. Ideas? (Ubuntu 18.04, the other two are 2080TI)

< here is the full xorg.conf

# nvidia-xconfig: X configuration file generated by nvidia-xconfig
# nvidia-xconfig:  version 418.88

Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0"
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
EndSection

Section "Files"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/psaux"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"
    # generated from default
    Identifier     "Keyboard0"
    Driver         "kbd"
EndSection

Section "Monitor"
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "Unknown"
    HorizSync       28.0 - 33.0
    VertRefresh     43.0 - 72.0
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    BusID          "PCI:b3:00.0"
    VendorName     "NVIDIA Corporation"
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

When using Nvidia's default xconf, I see that the BusID of the 2080 is

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "GeForce RTX 2080 Ti"
    BusID          "PCI:101:0:0"
EndSection

Which is not at all the output of lspci | grep VGA

When I'm restarting I loss display, and have to enter recovery mode and create a new xconf