Scythe Zipang SCZP-1000 Ultra Low Noise Heatsink Review
 

If you need a silent heatsink, and I do mean silent, the Scythe Zipang (SCZP-1000) is the next best thing to a passive block of aluminum (the only truly silent option). What makes the Zipang quiet is a 138mm wide fan that spins at a lazy 1000RPM.

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