[SOLVED] Is this schematic the correct way to adjust the speed of a 4 wire CPU fan? If not, would you please edit the schematic?

[s355]

https://imgur.com/X2Gr1

View: http://i.stack.imgur.com/X2Gr1.png

 

[JohnBonhamsGhost]

what are you trying to achieve with this fan?

if you only want to control the speed of a basic 4-wire Pulse Width Modulation(PWM) fan,
just plug it into a 4-pin PWM header on your motherboard
and set a custom fan speed curve either in your BIOS or your motherboard control software.

or are you looking to modify this fan for some other non-basic customized use?

 

[s355]

This fan is being used outside a PC. I am trying to make a Off/Lo/Med/Hi switch for it.

 

[JohnBonhamsGhost]

years ago there were quite a few molex powered fan switches available with a built-in controller like what you are looking to achieve.
perhaps you could still find one of those around somewhere?