Actually they won't. Ever open up a fan? They use electronics, so the speed is probably constant, depending on the circuitry. More voltage will just burn up the chippies inside.Just don't connect them to supply > 12V, Then they will spin faster and possibly burn useless.
Good luck
That's great to know, I've done that many-a-time before (luckily without any problems) but will be careful not to do it again.spin them up. The counter EMF from the spinning blades will blow them faster than you can say stop. Been there, done that.
by Jake Hertz
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