1. Make sure you have the latest Intel and Nvidia drivers.
2. Right click desktop > Nvidia Control Panel > Manage 3D Settings > Global Settings > Preffered Graphics Processor > Select High Performance Nvidia Processor
More info on Nvidia Optimus:
http://www.nvidia.com/object/optimus_technology.htmlIf you want to set it so only on one program go to program settings and select the program and the NVIDIA GPU.
By default, NVIDIA card will only activate when you open a DirectX game.