How can I make my computer use NVIDIA GPU instead of Intel GPU?

Yeah I made it run. I have a laptop using Nvidia Optimus. No matter what a set for r.GraphicsAdapter Unreal always choosed Intel HD 4600. I noticed in logs that it might be because there is in fact no output on GeForce graphic. All output goes through Intel so all devices are connected to it.

So I made a fake display connected to GeForce acording to this: http://www.helping-squad.com/fake-connect-a-monitor/

Now when there is an output on both adapters UE choosing GeForce finally!

Cheers