Dual monitor gaming(different GPUS, Nvidia)

Hello, i've set up my pc with two monitors using different GPU's. One is mainly for just browsing or watching movies and the other one for gaming so i have a strong primary card and a weaker secondary.

the issue is when i'm starting battlefield or other games as the game somehow tries to start using my older card. and yes i've the stronger card to be used as my primary display, but is there anything else i can do to make the rig recognize that i wanna start games with the primary card?

Using win 8.1 PRO 64bit

 

I suggest never using your slower card for video, configure it as a physix card or remove it.