Ubuntu: Switch from Nvidia to Intel graphics?

Solution 1:

To achieve what you want, you will have to install the proprietary NVIDIA drivers and Optimus.
After that you can switch between the graphics from NVIDIA X Server Settings PRIME Profiles.
Assuming you have a NVIDIA GEFORCE 400 series adapter or newer execute these commands :

sudo apt-get update
sudo apt-get install nvidia-352 nvidia-prime
sudo reboot  

Update addressing your response to having problems with 352 drivers

Use another method - first uninstall the formerly installed NVIDIA drivers.
Highlight the Ubuntu entry in the GRUB boot menu and press the E key.
Add nouveau.modeset=0 to the end of the linux line - press F10 to boot.

On login screen press Ctrl+Alt+F1 - enter user name and password - execute :

sudo apt-get purge nvidia*  
sudo reboot  

Now install the NVIDIA drivers 358 from the Proprietary GPU Drivers PPA.
Highlight the Ubuntu entry in the GRUB boot menu and press the E key.
Add nouveau.modeset=0 to the end of the linux line - press F10 to boot.

On login screen press Ctrl+Alt+F1 - enter user name and password - execute :

sudo add-apt-repository ppa:graphics-drivers/ppa
sudo apt-get update
sudo apt-get install nvidia-358 nvidia-prime
sudo reboot

Solution 2:

Nvidia settings is available in software center. Install it if not already installed.

sudo apt install nvidia-settings

Now open it by running this in terminal

nvidia-settings

From there you will be able to select which GPU you want to use (Nvidia/Intel).

Go to PRIME Profiles -> Select the GPU you would like to use -> Choose Intel (Power Saving Mode)