Water cooling is a great way to keep your computer super cool and super quiet, but it can cost a lot of money. Corsair's Hydro series makes water cooling easy with inexpensive, maintenance-free units that take just a few minutes to install.
Water cooling is great, but it takes a ton of upkeep, costs hundreds of dollars, and comes with a risk of drowning your computer if you make a mistake (yeesh!). Corsair's Hydro series -- made up of the H100, H80, H70, H60, and H40 -- makes water cooling simple. Just install the water block like you would any other cooler, and install the radiator on the top of your case (if you have the 120x140mm H100) or the back exhaust fan (if you have the 120x120mm smaller models). The fans will keep the radiator cool as the water pumps through it, giving you a quieter computer with lower CPU temperatures.
You'll still have to compromise a bit on noise, since you are still using fans, and Corsair's stock fans are quite loud. You can swap them out for something quieter, but the H100 and H80 also come with a handy feature that lets you run the fans on "low", "medium", or "high" speeds, which you can adjust depending on your needs.
If you're looking for a silent system, go with the lower, quieter setting; if you're overclocking and gaming, go with the higher, louder setting. Alternatively, you can do what I do and get an external fan controller and use that to control the cooler's fans instead. That way, you can have it quiet when you're just browsing the web, and louder when you need the performance boost.
I've been using the H100 for about a week now, and my experience has been very good. My temperatures are a bit lower, though probably not enough to overclock my system any further (obviously, your mileage may vary depending on the CPU you're using, your case, and the cooling system you're currently using). The main benefit I'm seeing is in the realm of noise -- coupled with the H100's fan controller (or an external one), you can decrease the noise in your system quite a bit.
If you're sick of your computer sounding like a wind tunnel, or if you just want some extra overclocking headroom, check out the H100 or one of its smaller cousins. See the video above for a look at the hardware, or hit the link below to check out the specs on Corsair's website. The H100 runs for about $160 in Australia, while the other models cost less as you go down the chain.
Corsair Hydro Series CPU Coolers [Corsair]