During the YOLOv3 deep learning setup, have to make sure that your nvidia-smi command is working fine and proceed to the next leve,
$ sudo nvidia-smi
Open your darknet "Makefile" and check the configuration looks like below, If you did not set the nvcc in your $PATH can set the direct location of nvcc bin file,
Build the darknet,
Choose the number of GPUs based on which are available in your machine, I have 2 GPUs in my machine.