RIFT looks to benefit a little bit from 2-way SLI, but there doesn't seem to be any real change with 3-way.
RIFT w/o SLI
RIFT 2-Way SLI
RIFT 3-Way SLI
If you look at the green overlay on the images you can see the percentage of load that's being produced in that particular scene. Pay no mind to the VRAM numbers because different things were running in the background on certain screenshots and contributing to that. This was just a quick test in the starting area with everything on max, but because I don't really multibox this game I can't say how SLI affects being in a location like a major city or a dungeon/raid with multiple characters, or if there are any known side-effects. Someone else may have an answer for that, though.
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