Can fans be run at <5V?

[Rileyrr]

So I have this Sunnon blower which moves a lot of air and is on the noiser side. I have it currently hooked to a FanMate 2 and running at the lowest setting (~5V) and it still moves a good amount of air. There is a slight buzz to the fan that decrease with speed, so I was wondering if I can run it at <5V? Basically, I have a 5V harness open (compliments of my Zalman VF700-Cu) which I could plug the FanMate 3 pin plug into. Theoretically I could then run the fan at <5V. Is there a problem with doing this?

 

[Rileyrr]

OK, so maybe I'll answer my own question. I found this on ocforums:

Most big fans don't run at even 5 volts, let alone start up on power-on. 6 volts is the safest IMO, but some big fans recommend 8-13 volts for operation. They don't change the voltage internally to get a certain RPM at 12 volts, it has to do with increasing/reducing the 'winds' (wire) on the armatures (thats what they're called in, umm, non-brushless motors).

When you run a 12 volt fan below 5 volts, it stops, but its still using energy. That energy is basicly frying your fan's electronics, if not all at once.

So, basically, bad idea. LOL

 

[Jeff7]

Good way to find out - try it.
I have a 12V Panaflo 120mm fan that will spin at 3 volts. Not many can manage that though.