<div dir="ltr"><br><br><div class="gmail_quote">On Tue, Oct 14, 2008 at 8:41 PM, Raphael <span dir="ltr"><<a href="mailto:rpooser@gmail.com">rpooser@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
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If you have a motherboard which is more than two years old, like me,<br>
chances are none of your ports are PWM controlled and they simply put<br>
out a constant 12V (three pin connector) or only the processor fan<br>
header has PWM. In that case if you really want PWM control there's an<br>
easy howto I used from bit-tech:<br>
<a href="http://www.bit-tech.net/modding/2001/12/03/pwm_fan_controller/1" target="_blank">http://www.bit-tech.net/modding/2001/12/03/pwm_fan_controller/1</a><br>
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raphy</blockquote></div><br>Nice. If it were me, I'd complicate it a bit more and use an atmel avr tiny to do the same thing. Then, you have the ability to reprogram it to your whims and no potentiometers are needed. You could even change the ramp rate on the pwm to be completely non-linear for your specific needs. The ATtiny24 could do the job, has an onboard temp sensor, built in PWM, and only costs $1.91 from digi-key.<br>
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