smc fan control not running fans full speed

I'm just a bit irked that Slashdot posted this today. Varies by fan of course, but this probably won't drain your battery any faster than plugging in a flash drive and pulling a few files from it. Notebooks, on the other hand, tend to use very small fans such as 40mm units, which have a power draw in the half-watt range at full tilt. There are fans out there that draw 12w and up, but those tend to be the high-speed 120mm fans that can do serious damage to objects that happen to get in their way.

I've seen numerous desktop-sized fans that use quite a bit more power than a notebook hard drive, which (in my experience) draw 2.5w or less (ie, you can power them from a USB port with no extra plugs). The voltage control almost certainly works on a percentage, but even if not, there's only so much available to give it - you can't just pull random extra voltage in from somewhere to overvolt the fan.Īs to the relation to a hard drive. The app just overrides the software control telling it to throttle the voltage until it hits near a certain RPM. It usually takes 5-6v to get them spinning and overcome inertia, but after that you can drop it down to 4v or so to keep it going. Some people who use their laptops as DTR machines will have them under a constant heavy load (and then run folding in the background, just to make sure their batteries never stand a chance), and their fans aren't tearing themselves apart.īasically, fans can be fed anywhere from 0 to 12 volts (maybe laptops are 0-5v, but it's pretty standard). The software won't throttle the fan faster than it was designed to go, and all fans are designed to be able to sustain their maximum rotation speed until they reach their MTBF. Well, desktop fans have yet to rip themselves apart.

Smc fan control not running fans full speed