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fan speed control?

Discussion in 'General Hardware' started by Darkgundam111, Aug 13, 2011.

  1. Darkgundam111 New Member

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    I have this fan http://www.mwave.com/mwave/SKUSearch.asp?px=DS&scriteria=AA79186

    plugged into my motherboard's 3 pin (jsfan)

    as i have googled, it requires the 4th pin before fan speed can be controlled. however, i am seeking a way to do so perhaps someone knows a way to?

    I would like to increase the speed of the fan, it seems to be spinning very slow.
  2. LordJummy

    LordJummy New Member

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    Get a resistor cable that can lower the power output to the fan.
  3. twicksisted

    twicksisted

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    how would adding a resistor to lower the power to the fan increase the fan speed?
  4. mlee49

    mlee49

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    The only way I would suggest getting your fan to run as fast as possible is to connect it directly to the power supply. You may need a MOLEX to 3 pin adapter, but it may also come with your fan.

    Depending on your mobo and where it's connected it may be throttled down already. The 4th pin your referring to is for PWM or Pulse Width Modulation to be a bit more active with it's powering scheme. A 3 pin power adapter can have the voltage dropped to make it run slower than rated, and some mobo 3 pin headers do that(in the BIOS).
  5. LordJummy

    LordJummy New Member

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    Whoops you're right. I thought I read "Decrease". My bad bro!

    Sometimes I see or hear what I want to see or hear lol
  6. sneekypeet

    sneekypeet Unpaid Babysitter Staff Member

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    Does the bios not offer fan control for that header?
  7. Darkgundam111 New Member

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    i am not sure where to look for the fan settings in the mobo bios actually. perhaps it is in there. i have a biostar TA790GX XE
  8. newtekie1

    newtekie1 Semi-Retired Folder

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    Plugging a 4-pin fan into a 3-pin header will make the fan run at full speed(assuming there isn't some setting in the BIOS that controls the fan speed via voltage). So there probably isn't a way to increase the fan speed, it is just a slow fan.

    Edit: I just looked at the manual for your board and there is something in the BIOS under the Advanced menu called Smart Fan Configuration. However, it looks like it only affects the CPU fan header, and is disabled by default. So if the fan is plugged into the jsfan header, it is getting full power, and going as fast as it will every go. The fan just isn't a high speed fan, it is built to be quiet, not fast.
    Last edited: Aug 13, 2011
    Crunching for Team TPU More than 25k PPD
  9. Darkgundam111 New Member

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    But looking at the fan spin seems far too slow for the specs that it has, which makes me believe that it's not running at full speed.
  10. newtekie1

    newtekie1 Semi-Retired Folder

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    There is a H/W monitor section of the BIOS also that shows the RPM of the fan connected to jsfan1. Go in there and see what RPM it is running at. If it isn't running at 1500RPM +/- 10% then either the fan header is busted and isn't supplying the correct voltage, or the fan is bad.
    Darkgundam111 says thanks.
    Crunching for Team TPU More than 25k PPD
  11. Darkgundam111 New Member

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    not sure what happened but i opened my case and checked the fan then closed it up and turned it on and its spinning at full speed now :) and i checked the motherboard monitor and it showed the max speed 1500 :) thanks guys
  12. Hockster

    Hockster

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    Darkgundam111 says thanks.
  13. Darkgundam111 New Member

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    oo cool will consider getting one of these.

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