New power supply for sli 770's?

ghostarcher12

Honorable
Dec 25, 2013
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10,640
I currently have a corsair cx750 and I'm not 100% sure it will work with another 770. What would be the best power supply for it, assuming I run two 770s and a 4770k @4.4Ghz?
I like corsair and I was thinking maybe the rm850.
Something modular is preferred.
Thanks.