Review on Quiet Scythe Kaze Flex 120mm Fan - High-performance Case/CPU Cooler Fan with PWM and RPM Range of 300-1200 by Wayne Martin

Something that isn't listed on the product and I didn't find out until I've already bought 3 of these fans for my new build is that the specs come in as 300-1200 RPM / min PLUS OR MINUS listed are 200 rpm. Both of my fans weren't spinning below 600-625 (300-325 RPM higher than the specs on Amazon and 100-125 RPM higher than the tolerances on the box!) RPM at minimum speed, set in the BIOS what is significantly louder than idling from 300-350 when switching to a silent system. One of my fans, which was actually spinning at the advertised 300 RPM, was making a horrible rattling noise. So these fans look good and are mostly quiet for a good price but have VERY wide tolerances. For comparison I bought 4 Noctua fans to replace, 3 different models and they all ran within 50rpm of their rated min and max speed. This is how a product should be made. For the price and if you aren't focused on building a completely silent system these fans should be fine, but if you're looking for absolute silence then you might want to look elsewhere as you'll be lucky if your fans are actually that quiet rotate as specified in the Revain specifications.