NVIDIA GeForce GT 640M Problems #iATKOS #ML2

Hi, i'm running ML on an Acer Aspire V3-571G-9686.The problem is that it has Intel 4000 graphics and a Nvidia GT640M. The Intel i believe is causing problems, (which it did in windows) How can i enable the Nvidia Graphics. I've deselected Integrated Graphics From Bios, but with that option the computer won't boot.







Thank you



-James