A/V 2 Monitors, 2 GFX Card's, Which Plug?

So yeah just gone multi monitor for the first time ever and which graphics card should my monitor be in? Should I have 2 monitors in 1 card, or just 1 in each?

I ask because when I first put it into my second card, it tried to turn off SLi, and I most definitely want it on! This makes me think should I have both monitors in the SLi focus card, but then again since I renabled the SLi, everything seems to be all perfect again.

Any adivce?

 

Plug both monitors into the primary card.

Moriquendi

 

Cheers babe