To get a 240 mm rad on a video card for closed loop you will need to buy special brackets to allow for mounting onto a gpu. for the 770 price, you might as well have just bought a 780, as you will not get a 770 to surpass the 780 by overclocking its' face off.
the accelero hybrid is better than the kraken, but still has only a 120mm radiator, but the fan on the shroud, combined with the additional installation of heatsinks allows for crazy levels of overclocking vs just water cooling the core