6970 Xfire enough for 1560x1440?

http://www.overclockers.co.uk/showproduct.php?prodid=MO-013-HO

This monitor should be arriving at some point today and at the moment I'm running 6970 crossfire with an i7-960 @ 4.5ghz. Both cards are reference models.

I mainly play Starcraft but I do delve into games such as bf3 and others. The main use of the monitor will be for gaming and graphic design work. Which is why I picked this over the dell as it has much lower input lag. Not to mention a lovely glossy screen and half the price tag.

Now I'm still wondering if 2gb Vram will be enough at this resolution? Or will I have to pick up a 7970 or a 580?

Thanks.