Possibly a dumb question, but as someone who hasn't run an SLI setup since the 3DFX Voodoo days I was curious about how the system treats the memory of the cards in question. I've currently got a 560ti and bought a used second one. They're both 1GB cards, but I wanted to know if you effectively get 2GB of video memory or not. If someone can explain how it ends up working, that'd be rad.
In SLI/CF, the amount of VRAM is always equal to the smallest card. Never combine. Thus, in your case, it's 1GB.