*Review: Frostytech (
http://www.frostytech.com/articlevie...ticleID=2249)*
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Most heatsinks emphasize the downward directed airflow that is useful for cooling all the little electrical bits around the CPU socket on a motherboard. As you're probably well aware, motherboard manufacturers like ASUS, MSI and Gigabyte are slapping tiny passive heatsinks on the MOSFETs and power circuitry that ring the processor, and much larger passive heatsinks on the northbridge chipset.... all of which is designed to make use of that exhaust airflow from a CPU heatsink. It's a parasitic relationship that many a motherboard is built upon, and it's a good one because no extra noise is generated in the PC case from small chipset fans.
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