I've been looking to upgrade my current GPU's to something a bit more robust and modern, considering the hardware requirements that SC is going to be needing. I currently use two GTX 560 Ti's in SLI, which are starting to show their age with some of the more recent games like BF4. So I started looking around at what is available, and I've come to a crossroads with the GTX 690 and the GTX 780 Ti. On paper, the GTX 690 looks the better card. But according to folks from other hardware forums, the 780 Ti is the better choice. So for reasons that I don't quite understand, the GPU with the smaller price tag and stats (the 780 Ti) is the preferred card. Maybe someone could clarify this? I would be purchasing two of these cards and running them in SLI, but before I do that I'd like to really know what my money is going towards.

These are the respective specs from the GeForce website:
http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-780-ti/specifications
http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-690/specifications

Thanks in advance.