I have a Samsung RC720 notebook with Intel Integrated Graphics and NVIDIA GeForce GT 520M. As you can see it has two video adapters and Optimus is supposed to switch between them. But when I choose dedicated GPU in NVIDIA Control Panel and try to run, for example, GTA IV, it uses integrated graphics and I get very poor performance. I have already installed last NVIDIA and notebook drivers, chose high-performance in NVIDIA Control Panel, tried to execute with "Run with graphics processor..." context option and so on. Thanks for help.