The Hi mode actually goes up to 3800 RPM. 3000 RPM is the Lo
mtrai • May 10, 2018, 6:11 PM
What the other reply stated...it allows for a higher max fan RPM.
Valkaro • May 10, 2018, 6:59 PM
It is a physical switch on the bottom or top of the cooler(depends how you mounted it). It is really small, and pretty hard to switch because it's kinda inside the fan. If you mounted it correctly it's on the bottom of the fan