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3-pin Fan Wire Mod for reduced voltage

The svc item is just 3 diodes in series with the red wire (+12V for the fan header). Each diode presents a constant voltage drop of ~0.7 each, three create the 2V drop. The frozencpu item appears to be a sandblock resistor (again wired in series with the red wire), which will present a voltage drop proportional to the fan current. The motor current is not linear, so predicting the current drawn at a lower speed is not easily done - the diodes present an easy solution to the problem by providing a constant voltage drop. Some generic diodes from ratshack rated for at least 1A should do the trick, just add as necessary to reduce speed. Zener diodes can provide an exact voltage drop, but these will need to be properly sized (rated wattage) to prevent it from overheating & burning up.

Guide: http://www.instructables.com/i...iodes_for_Fan_Control/
Just ignore the right-half of the schematic (actual fan control is on the left). The diagram uses a switch to select how many diodes are in series with the fan motor, you do not need a switch if you know what voltage you want to run the fan at.
 
It looks somewhat more complicated than I expected, but I'll give it a shot. The video might help!

Interesting, I didn't know the two are using different methods to reduce the voltages. Learn something new everyday. Thank you much.
 
It's not too complicated, the schematic presented is however. Here's the simplified version (no switch) - fan.jpg. Use however many diodes you need (each provides 0.65 volts drop).
 
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