For best temps, you would want a water block in full loop. But otherwise, the stock cooler is more than enough for any graphics card.
There are only 2 times when you need better cooling. If you find the stock cooler to be noisy (most folks that go water do it for this reason) or for the few and proud, the ones that overclock the card until it cries for mama.
Any other use, and the cards stock cooler is plenty.
If you find the noise bothers you, then you can try using MSI afterburner to play with the fan speed before you try water cooling. This is a step in between. And really, if you water cool, it is a good idea to have several years of either automotive cooling experience, or plumbing experience before you try it. And it will be probably around $500 in just cooling to do a proper loop. You pretty much have to have a RR Merlin of a graphics card to need water cooling for sound only.