After market fans are not something people think about as an upgrade, unless they bought a big heatsink that doesn’t come with them or an existing fan takes enough damage to stop working properly.  Those who are shopping for fans tend to be looking for quieter operation, more airflow or both and they should consider the Zalman ZM-F4 135mm multipurpose fan.  Large enough to move air quietly, especially with the silicone mounting pins and built so the screw holes are in the same place they would be on a 120mm fan gives you an extra 1.5cms without extra work.  Check out Legit Reviews results from testing the fan here.

Zalman's 135mm fan can find a home almost anywhere - Cases and Cooling 2

"We’ve visited similar offerings from Zalman’s Computer Noise Prevention System (CNPS) products with the Zalman ZM-F3-FDB & ZM-SF3, along with the CNPS 9900 MAX. We at Legit Reviews have come to respect the Zalman products we have seen since they perform admirably and live up to their claims. Today was no different. Zalman’s ZM-F4 Multipurpose Fan was probably one of the best fans I have ever run into. Its sound was as smooth as butter. It outperformed most offerings on the market. It also did so while still remaining quiet and affordable…"

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