Scythe Ashura / Katana 4 CPU cooler review
 

The Katana 4 performs better than the Cooler Master Hyper T4 and Hyper TX3, both in terms of cooling and noise. The Scythe Ashura cools very well when its fan is turning at high speed, but it's also noisy. When the fan is at low speed, the cooler is completely quiet, but also cools poorly.

http://uk.hardware.info/reviews/4292...-cooler-review