When I installed the Nvidia Driver, my Ubuntu OS can not auto login without a display device.

Hello,

 My problem is that: 

 When I installed the Nvidia Driver, my Ubuntu OS can not auto login without a  display device. And the device Number is Geforce GTX 1070 Ti.

Now I want to run my application as a Server without any display devices,how i can fix it?

The install method used “apt install nvidia-384”

Either fake a monitor using the ConnectedMonitor option in xorg.conf (https://download.nvidia.com/XFree86/Linux-x86_64/384.98/README/xconfigoptions.html) or buy a headless dongle and plug it in.