Well, if it's your first time watercooling, a Rasa RX240 or RX360 kit would be great! If you're wondering, the difference between the RS and RX is that the RX is just a thicker radiator. The only negative I have on the Rasa kit is the tubing isn't the greatest, but it's very cheap and you can always buy your own. You can always upgrade components from the Rasa kit

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The CM Storm trooper offers great water cooling options. If you were thinking to do just a CPU loop, go ahead and get yourself an RX240 or RS240. If you were thinking of doing CPU + GPU with a little overclock, get yourself an RX360. Most people will say get a 360 radiator + 240 or 120 radiator, but it all depends on how you feel about your temps.