CPU Fan running at speed the whole time....

Heys guys, my problem is exactly as it says above. Finished my first ever build today(Build here) and once it booted the cpu fan, which is plugged into the CPU fan header(3 pin connector into the 4 pin cpu header) has been running at full whack the entire time. As you can imagine its quite loud! The CPU cooler is a Thermaltake Contac 16. Ive spent most of the trying to figure it out but havent gotten anywhere. The fan is cooling the CPU(idles at around 34c).

To get around it, I've plugged the CPU cooler into one of the chassis fan headers(seems to run fine there, I can control the rpm through the motherboard, just cant control the cpu fan header whatsoever).

Ive reset the CMOS, unplugged, plugged in everything I can think of. At my wits end, would be very much appreciated if anyone could help!
7 answers Last reply
More about cpu fan running speed time
  1. if the fan is has a 3 pin connector then the fan is not a PWM fan. for your board to regulate the fan correctly it would need to be a four pin fan. the fourth pin allows for PWM power management.

    3 pins = 1 pin positive charge. 1 pin negative/ground. 1 pin tachometer/RPM reading

    4 pins = 1 pin positive charge. 1 pin negative/ground. 1 pin tachometer/RPM reading. 1 pin power management allowing for RPM control.
  2. I knew that the 4th pin allowed for PWM but I have 2 other fans which are both 3 pin and I cant control both from the motherboard
  3. I'm assuming you actually meant to say you "can" control them from the mother board. the 4th pin allows for AUTO fan control what you need to do to the other fans is MANUAL control. the CPU fan should be auto controlled due to the rise and lowering of CPU temps.

    EDIT: that is unless you want it to scream on full speed all the time.
  4. I've spent most of the day trying to get the CPU fan to adjust itself according to the temps but have had no luck. Fan XPERT + doesnt allow me to adjust the CPU cooler(plugged into the CPU fan header) speed at all, but I can adjust the other two 3 pin fans plugged into CH1 & 2 respectively. Im lost.
  5. OK i must not be explaining good enough. You need a 4 pin fan. That will be the only way you will be able to adjust the fan from that fan header.

    Being a 4 pin header different rules apply to it. On a 4 pin header, to be able to use any type of fan control, you need a 4 pin fan.

    Hope I was more clear this time. :)
  6. i apologise, heads melted at this point! So would you would suggest getting a new fan for my cooler? Cant listen to it running at full whack the entire time!
  7. Yes that would be the best fix to your issue.
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