M4A785D-M Pro fan speed question

Hello. Earlier today my trusty old server started smelling like old fish, and a few seconds later turned off.
Fast forward 4 hours, and I'm writing this from the server. New (used) parts include an X4 940, 8GB ddr2 and the asus M4A785D-M Pro motherboard.
The bios has a feature called Q-fan to regulate fan speed on the cpu. This however seems to have no effect whatsoever. The fan keeps spinning at 2.6K rpm even when the cpu cores are at 31C temp and all cores are idling at those nice 800mhz.

I tried downloading the cool and quiet application from asus, but that turned out to just be a really bad copy of cpu-z.

Is there any way I can get the fan speed regulated using that Q-fan feature, or does it require a pwm enabled fan?

Am using the Zalman 9700LED from the old Nforce based 550 system.

On the old system the fan was almost never spinning, and never ever running at full speed. The noise from the fan at this time is really annoying, and I need it muffled somehow.

ps. speedfan isn't an option. It doesn't seem to like my Windows 2008R2 very much. The service creation is broken.
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More about m4a785d speed question
  1. There must be a setting in BIOS that sets the CPU fan outlet to PWM , DC or other. Try that first maybe is on default DC
  2. I tried googling Q-fan a bit after writing this, and it appears Asus has gone cheap. It only supports PWM. The Biostar board I had before let me pick between pwm and voltage (or disabled), so I assumed that was the standard thing to do.

    Maybe I'll install a Scythe Ninja or something when I get home - then I can use one of the pwm fans I've got spare.

    Unless someone clever comes up with a better idea.
  3. try and change only the Fan (if its the same size) but i have checked and the Zalman one is PWM. See maybe there is a BIOS revision that has some relevant changes relating to FAN control. Flashing wouldn't hurt.
  4. Try deactivate the QFAN maybe then you have activated other manual options.
  5. No the fan's not PWM. It's a fairly old version (2006 I think). I don't have any 92mm fans with PWM support. In fact I only have the zalman one, and an old thermaltake from 2004 which obviously doesn't have PWM support either.
    I do have like 10 different 120mm ones though, and some have PWM support I think.

    As for bios update - did actually think of that just now. It's already running the latest version.

    Anyhow, I'll pack up here at work (everyone else is already gone anyway) and go home. If nothing else happends here, I'll at least let you know what I decide to do.
    Worst case scenario, I'll use a molex to 3 pin fan converter and run the fan staticly on 7 volts. But that really is the last resort option.
  6. PWM has 4 wires on the connector.
    1 GND Black
    2 12 V Yellow
    3 Sense Green or tachometer
    4 Control Blue
    Note that colors could change (red and black always remain)
    The old one 3 wire one (Red+12v Yellow tach Black gnd)

    3-pin: the third pin is for RPM sensor. So, you can control the speed according to this sensor's reading.

    4-pin: the fourth pin is for PWM (Pulse Width Modulation). This adds temperature into the monitoring

    3 pin should work on a PWM outlet but it depends how the BIOS handles the readings as sometimes they are incompatible or interpreted the wrong way.
  7. I know that stuff ... that's why I knew it wasn't a pwm fan

    Anyway, at the moment the noise is no longer a concern. Turns out replacing the motherboard and network adapters has wrecked my rras setup.
    I can't add any interfaces save for 'internal' and even removing and reinstalling the role service as well as resetting ipv4 and routing in netsh has resulted in nothing good.
    In fact it's gotten worse now, as I have to disable and reenable the outgoing lan adapter before it gets a valid dns for some reason.

    in shot - I know the stuff you're trying to explain, and all of a sudden it isn't even important to me. Sorry for wasting your time though.
  8. Problem still not solved, but spent the night reinstalling a fresh windows server. At least the routing now works. Too bad mysql doesn't ; homepage no workie without :(

    Anyway I tried muffling the sound by messing a bit with wires and stuff. Ended up melting a wire and shortcircuiting the smbus (which survived for some odd reason). Guess I shouldn't do that at 3 in the morning. Smells horrible when the insulation is melting.

    Anyway, now I'm again reminded why I hate asus motherboards.
  9. Best answer
    Looks like you havin a bad day there. No probs i had FAN issues myself and blow the FAN controller on the mobo and had happy days (not intentionally do with all the measures taken) and bought 2 Akasa Viper 120mm fans with PWM. I learned my lesson in modifying fans :) and never blamed asus and about the rest well its only windows Plug and Pray
  10. Gonna put you as best answer. Not that it solved my problem, but as the only answer yours must be the best by default.

    Eventually I ordered a new cpu cooler and new chassis fans with pwm. Problem solved. Just sort of a waste of resources when I've got 10+ fans and 2 quality coolers spare that simply don't work in this piece of *** board.
  11. Best answer selected by neiroatopelcc.
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