InWin Classic Series 750W 80 Plus Platinum PSU Review

Fan Speed

When testing in a power supply laboratory it is difficult to take fan noise readings as the noise from the Sunmoon test equipment and air conditioning corrupts everything. The next best thing in our circumstances was reading off the fan speed with a tachometer to get an idea for the noise. The ambient temperature during testing held constant at 22 degrees, with 1 degree of variation. Each power supply had a consistent time period of 5 minutes to stabilise between each load scenario. 

In my experience the following general relationships apply between noise levels and fan speeds, though it can vary greatly between the type of fan used.

• Below 800 RPM – Inaudible/Silent
• 800 to 1000 RPM – Barely audible
• 1000 – 1200 RPM – Audible but still quiet
• 1200 – 1400 RPM – Moderately noisy
• 1400 – 1800 RPM – Noisy
• 1800 RPM or higher – Intolerable

It wasn’t a particularly hot day in the office today, only 21c so we don’t think the fan had to work as hard as usual. Even then, while we had the PSU at full load for quite a while, the fan didn’t even break 400RPM, to say it was quiet would be an understatement and while many PSUs have a passive mode for absolute silence, the C750 was quiet virtually inaudible anyway.