Look mate , the reason why closed loops can't beat the custom loops in performance is because of the weak and crap pumps , rads and cheap tubing used. Their coolant in most cases therefore remains hotter than what it should and travels slow. Many Closed loops ( Especially from Corsair ) are cheap because of reasons mentioned above. Custom loops are far better and the choice of pro overclockers ( Liquid Nitrogen for world record breakers though ) This is because of the much superior pumps ( most have the capacity to push water through multiple rads and waterblocks ) , better rads ( which keep the water cooler ) and far more better waterblocks , wider tubes and much more. However for the one who struggled during assembled a PC , Closed loops remain much better. They don't need refilling , priming , maintenance , etc. But for performance Custom loops is the way to go. That was until these two were mixed up by the Swiftech H220. This series had the ease of closed loops and power of custom loops ( almost ) ElMoIsEviL has a good choice there , the H220 is the best if you want to cool anything else too , or if you want the ease. I am sure the XSPC Raystorm or the Swiftech H220 are the best your money can buy. Just don't forget the thermal paste and choose a good one ( Antec Formula Nano 7 , Artic MX-4 are on the top of my list ) Also if you wan more performance , or if you find the temps high above expectations ( You probably should not ) Set a Push/Pull Configuration. That way , you will drop temps. I hope you choose something you will be happy with , in the end. Also consider the H60's and H80i's if you did not like my suggestion. And yeah kudos to bjaminnyc for asking what case you have ( since no one else did
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