Nvidia GeForce 830M/840M is 'Maxwell', GTX 860M is 'Kepler' - video card
GeForce 840M | Product Images | GeForce
The graphics option vanishes after installing lilu.kext and whatevergreen.kext. The graphics now is showing 7 mb although i have 2gb Nvidia GeForce 840m. So i installed Nvidia web driver through terminal(because normal