CPU Chassis Fans Running at High RPM/ Very Loud

So I installed an ASUS M4A785-M motherboard and got it to run. The only problem with it now is that the CPU and the chassis fans run way too fast and are really loud (I have to turn up my music pretty high to drown them out).

From the unplugging and plugging in I've tested, it seems that one of the power connector slots for the fans outputs more voltage. Right now the CPU is running at ~4500RPM, and chassis fan running current at ~2700RPM. And when I switch the power connectors, they both switch RPM (i.e: CPU fan runs at ~2700RPM and the chassis fan will run at ~4500RPM).

I have the AMD Quiet-N-Cool and Q-Fan settings enabled in the BIOS, but those settings haven't fixed it. I've also tried installing some ASUS temperature/fan control software, doesn't seem to help. Is there something in the BIOS that controls the voltage for those two power connectors?
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More about chassis fans running high loud
  1. The CPU_Fan must be always connected to the CPU_Fan header.

    Yes, get into the BIOS and there are settings for the 'CHA_Fan' 'PWR_Fan', that you can control. Then keep a close eye on temps. - change the fans settings if necessary.
  2. The good news is that the CPU fan is connected to the CPU header.

    The bad news is that there doesn't seem to be a CHA_fan or PWR_Fan option under the BIOS. The BIOS has this temperature and fan speed monitor and everything is good: everything is under 45 Degrees Celsius. And its reporting the RPMs I originally posted. Just really loud and annoying to hear two fans spinning at 4500 and 2700 RPM.
  3. In the BIOS do you have something like 'PC Health Status'? On my EVGA motherboard BIOS, this is where the fans speed controls are located (the fans plugged into the motherboard fan headers).
  4. Nope, the top options are:


    Nothing like "PC Health Status" on this ASUS board. The closest thing to a menu that manages fan and speed controls under Power. For me its Power>HW Monitor Configuration. But that only displays the CPU/MB/Fan's temperatures and RPM, doesn't really allow me to adjust it. I can either select if I want them to be displayed or ignored.
  5. Can you post the link to your motherboard's manual?

    Click on the "Download" tab>Select OS (I'm using Win 7 64-bit) > Manual > Scroll all the way to the bottom of the list to get the English manual.
  7. Thanks! On reading the manual, this motherboard has one CPU_Fan header, and one CHA_Fan header (see page xii of manual). Both headers marked '1' on page 1-7

    The CPU heatsink fan must be connected to the header marked 'CPU_Fan' - the other 'CHA_Fan' header may be used to connect a side fan (if you have one) or a top fan, or a front fan. The BIOS will control fans connected to these headers.

    Generally, I like to connect the rear fan directly to the PSU using a Molex cable, and run it at full speed for better cooling.

    See the note on page 1-29 "Only the 4-pin CPU fan supports the ASUS Q-fan feature".
  8. So I guess that explains why Q-fan (and probably Cool-n-Quiet) isn't working. So is there no way to adjust the speed of the fans to make it run quieter?
  9. Best answer
    abc617 said:
    So I guess that explains why Q-fan (and probably Cool-n-Quiet) isn't working. So is there no way to adjust the speed of the fans to make it run quieter?

    Yes. You can use a fans controller to control the fans speeds. Here are some examples:
  10. Best answer selected by abc617.
  11. Thank you!
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