Install Xorg 

sudo pacman -S xorg-server xorg-apps xterm

Start out by checking you driver: lspci -v | grep -A1 -e VGA -e 3D Then install the Nvidia drivers 
sudo pacman -S nvidia nvidia-utils nvidia-settings xorg-server-devel opencl-nvidia lib32-nvidia-utils 

mesa-demos includes glxinfo test your Direct rendering.
glxinfo | grep direct 

for opengl test it with glxinfo | grep OpenGL For monitoring your nvidia Gpu nvtop 
sudo pacman -S nvtop 

Run nvtop in terminal to monitor you gpu

sudo pacman -S nvtop 

For Nvidia automatic Xorg config file.
nvidia-xconfig

reboot your computer after installing Nvidia drivers.