Extra Graphic Display : nVidia GTX 1060 (laptop)
There are two display graphic cards on the same system, namely Optimus on laptop. The installation of nVidia display driver on Kali Linux 2018.4 is difference to Ubuntu 18.04.1 on the same system. You can refer to the link here for Ubuntu 18.04.1 even they are using the same version of nVidia display driver - Version 390.87 at the time of this writing.
Step 1 :
apt install nvidia-kernel-dkms primus bumblebee bbswitch-dkms nvidia-smi
Step 2 :
Reboot the system.
To confirm the installation.
Step 3 :
Install HashCat which does not require CUDA.
apt install hashcat-nvidia
Step 4 (optional) :
To install CUDA.
apt install nvidia-cuda-toolkit
To run program that requires CUDA.
That's all! See you.