Glacialtech Igloo 5610 PWM Heatsink Review
 

The Glacialtech Igloo 5610 PWM is a compact LGA775 Intel heatsink suitable for office work computers. It's 80mm fan is Pulse Width Modulation compliant, so Intel motherboards can direct it to spin only as fast as required (from a low 800RPM to moderately audible 3200RPM), thus keeping unnecessary noise down.

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