The NZXT Kraken X31 is smaller than its cousins, the radiator is a compact 120x30x155mm and uses a 120mm fan to move heat.  NXZT seems to offer proprietary controller software, called Cam software, but once you read the difficulties [H]ard|OCP had obtaining and using the software you will see why they recommend sticking with SpeedFan.  The performance is not quite as effective as most 140mm or 280mm coolers but on the other hand it operates at a significantly lower volume, 40.9dBA at most.   If you are looking for a decent performing and quiet cooler then check out the full review.

"NZXT is also moving some of its AIO cooler strategy into the realm of making it smaller and more efficient. The Kraken X31 ticks that checkbox plus a few others, such as software control, variable pump speed, 16 inch tubing leads, and a six year warranty. (Place your own "Release the Kraken," joke here.)"

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