2 screens will not do anything to performance as you cannot do nvidia surround unless that is what you intend on doing?
Even so you need 2 GTX 560Ti's to even think of 3 monitor setups with nvidia.
1 560ti will do ultra but in DX11 with added textures expect around 25-40fps.
Well im not planning to do three screens, but two will do just fine. im only going to run with one card for now gonna add bits of pieces into my system once i get the money for it.
Well if you actually find a way of getting Nvidia surround working from 1 GTX 560Ti, and also having the game across 2 screens with the screens bezels in the middle of your veiwing area you will see why.
But because this is not possible you will be gaming on 1 monitor even if you have 2.
Oh okay i now understand what youre talking about. So if i ran three screens i would need to go into SLI?
Yes and you would be better suited to the 2GB versions, however you will need a new psu and you will need an SLi bridge as i doubt that pc comes with one.
You will need a new psu when you buy a single GTX 560ti anyway...
Oh i have the 750 watt corsair for the single im pretty sure the sli will run well under that psu