Water cooling is something that keeps on puzzling PC newcomers: What do I need it for? What differs it from air cooling? Which of both is better? Does it fit on my CPU? What does "AiO" mean?
At the end of the day the choice between air and water cooling is mostly one of personal preference: Do you like a big chunk of metal on your CPU or are you more the tube-in-your-system kind of guy? And if it has to be a water cooler - what size should the radiator be? 120, 240, 280 or 360mm? This mostly depends on your CPU, and whether you want to overclock it. We recommend studying this video as it shows in detail what's important when choosing a water cooler.