Most graphically demanding game in existence?



It should be fine with the right setup.

Fresh air is key when producing that much heat. Try to have more intake fans than exhaust fans. If mounting a fan on the bottom or side-window of your case is possible it will benefit a SLI setup immensely.
 


I have a Thermaltake Core X9 cube case with two top-mounted 200mm fans.
 


Crysis 3 is still the prettiest game I've seen yet.