Reliable CPU fan speed controller?
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From: JD on 23 Oct 2009 21:31 I have a CPU fan that runs all the time at around 4,100 rpm. This is completely unnecessary when the weather is cool. I believe a speed of about 3,000 should be ok at present. Is there any such program around? I know about SpeedFan but I think it's a primitive piece of work. The CPU needs a delicate touch. I did a search and found http://wareseeker.com/free-cpu-fan-speed-control-software/ However it's hard to tell whether they are discussing the cpu speed or the fan speed. Anyone have experience of these? TIA
From: Paul on 24 Oct 2009 00:59 JD wrote: > I have a CPU fan that runs all the time at around 4,100 rpm. > This is completely unnecessary when the weather is cool. I believe a speed > of about 3,000 should be ok at present. > > Is there any such program around? I know about SpeedFan but I think > it's a primitive piece of work. The CPU needs a delicate touch. > > I did a search and found > http://wareseeker.com/free-cpu-fan-speed-control-software/ > However it's hard to tell whether they are discussing the cpu speed or > the fan speed. > Anyone have experience of these? > > TIA Have you looked at your BIOS functions ? Maybe there is an option in there to control the fan. Paul
From: JD on 24 Oct 2009 14:10 Paul wrote: > JD wrote: >> I have a CPU fan that runs all the time at around 4,100 rpm. >> This is completely unnecessary when the weather is cool. I believe a >> speed >> of about 3,000 should be ok at present. >> >> Is there any such program around? I know about SpeedFan but I think >> it's a primitive piece of work. The CPU needs a delicate touch. >> >> I did a search and found >> http://wareseeker.com/free-cpu-fan-speed-control-software/ >> However it's hard to tell whether they are discussing the cpu speed or >> the fan speed. >> Anyone have experience of these? >> >> TIA > > Have you looked at your BIOS functions ? Maybe there is > an option in there to control the fan. > > Paul Great suggestion Paul. I looked in the BIOS and found 2 options for the fan Fan Control - [Enabled} Lowest Fan Speed - [Slow] The first one had no speed control as far as I could see and was the existing setting since the motherboard was installed I set it to the 2nd one and rebooted. It was exactly the same as before - whizzing along at 4,100 + or - a few hundred. I did have this fan plugged into the right socket - it is right beside the CPU. I looked in Control Panel - Add-remove hardware and it was no help. Likewise in the Control Panel itself. Do you know of any other possible location for a fan speed controller? TIA
From: Paul on 24 Oct 2009 14:46 JD wrote: > Paul wrote: >> JD wrote: >>> I have a CPU fan that runs all the time at around 4,100 rpm. >>> This is completely unnecessary when the weather is cool. I believe a >>> speed >>> of about 3,000 should be ok at present. >>> >>> Is there any such program around? I know about SpeedFan but I think >>> it's a primitive piece of work. The CPU needs a delicate touch. >>> >>> I did a search and found >>> http://wareseeker.com/free-cpu-fan-speed-control-software/ >>> However it's hard to tell whether they are discussing the cpu speed >>> or the fan speed. >>> Anyone have experience of these? >>> >>> TIA >> >> Have you looked at your BIOS functions ? Maybe there is >> an option in there to control the fan. >> >> Paul > > Great suggestion Paul. > > I looked in the BIOS and found 2 options for the fan > Fan Control - [Enabled} > Lowest Fan Speed - [Slow] > > The first one had no speed control as far as I could see and was the > existing > setting since the motherboard was installed > I set it to the 2nd one and rebooted. > It was exactly the same as before - whizzing along at 4,100 + or - a few > hundred. > > I did have this fan plugged into the right socket - it is right beside > the CPU. > I looked in Control Panel - Add-remove hardware and it was no help. > Likewise in the Control Panel itself. > Do you know of any other possible location for a fan speed controller? > > TIA Maybe the next test, is to try Speedfan. If Speedfan cannot get any response from the fan, then it could mean there simply isn't a hardware feature there to control the speed with. (It could mean, for example, that you've mixed incompatible components together. Or that the motherboard makers are cheapskates.) The rest of this is some background. Mixing a three pin fan with a four pin fan header, may deprive you of a control method. And that is an example of how you can accidentally be stuck with a screaming fan. ******* The CPU fan header has a couple features to control fan speed. Back in the "three pin header" days, voltage control was used. The fan normally runs from 12V. But the motherboard could control the voltage, and deliver a variable voltage between 7V and 12V. This would take a PWM output from the controller, and require a MOSFET or transistor near the fan header, plus a capacitor, to convert the pulse width modulated control signal, into a voltage. It costs the motherboard maker some money to do that. X <--- RPM (from fan to motherboard, for monitoring) X ---> 7 to 12V to power fan X --- Ground If you're using Speedfan, Speedfan may find the registers that control the PWM output. The register can be programmed, and the hardware chip is then outputting a PWM signal. But if the motherboard maker wants to save money, they don't bother to install the interface circuit (the MOSFET and capacitor). Speedfan cannot tell those components are missing. So one of the checks I make, when someone has this problem, is to look at a picture of the motherboard, and see if the appropriate looking components are installed nearby. (Some general rules of thumb. Prebuilt systems from HP/Dell/Gateway are the ones most likely to have fan control per header. Which means they have the most fan control of all. On an Asus motherboard, the cheapest boards have no fan control. A board with QFan has the CPU fan controlled. A higher end board with QFan2, has two headers under control, one via CPU temp, one via chassis temp. So that should give some idea what to expect in terms of working channels. With the four pin fan header generation, you're much more likely to have a CPU fan control, so the situation should be getting slightly better as time passes.) ******* The second control method, is of more recent design. Both Intel and AMD now use four pin fan headers for CPU. The fourth pin is (what a surprise) PWM. What is happening in this case, is the responsibility for the MOSFET and capacitor, is now up to the fan manufacturer, as they're inside the fan. The motherboard has a fan controller interface on it somewhere (I can't say right off hand, where this one is located now). The logic signal output, running at perhaps 25KHz, is delivered on the fourth wire of the fan. The fan runs at full 12V all the time. The conversion circuit inside the fan hub, uses the pulse width of the PWM signal, to control the voltage delivered to the fan. That means the fan can run at 7V, using a circuit inside the fan hub to make the 7V from the supplied 12V. X ---> PWM (from motherboard to fan, 25KHz, indicates speed desired) X <--- RPM (from fan to motherboard, for monitoring) X ---> 12V DC (power from motherboard to fan) X --- Ground So as a consequence of having that fourth wire and control method, Intel recommends not attempting to reduce the 12V fed to such a fan. That recommendation, is so the MOSFET has sufficient signal applied, so it will be biased properly. Now, imagine what would happen, if you purchased an aftermarket heatsink/fan combo, with a three pin connector, and connected it to a four pin header. No PWM signal. No variable 12V. And hence, no control method. Again, programs like Speedfan will feel they're "dialing the knob", but nothing happens. ******* There is one other feature, which was used in the past with Intel fans. They had a thermistor in the fan hub. If the computer case air temperature rises, the fan is set to spin faster, based on the measurements by the thermistor. That feature does not lend itself to control by the user. Its purpose is to compensate for the worse cooling situation caused by hot case air. So if the computer has poor ventilation, the CPU fan may scream a lot more than it would in a cooler running case. Any other control method applied, multiplies its effect, by the effect provided by the thermistor. So if the computer case was very cool, the fan may hardly be turning at all. Speed = Voltage_controlled_speed * thermistor_set_speed Anyway, my next steps would be some Speedfan testing, and some visual inspection. Like, checking whether there is a three pin fan connected to a four pin header. On an older motherboard, whether the appropriate components are next to the three pin headers, and so on. As far as I know, there isn't a programmatic way of determining whether the controls are actually hooked up and working. A program could certainly observe the RPMs, and notice that nothing is happening, but I'm not aware of any program bothering to carry out such an analysis for the user. During the transition from three pin to four pin CPU fan header, Asus made some motherboards with dual control methods. The four pin header could be controlled as if it was a three pin header. There was a BIOS setting, that determined whether voltage control or PWM control was used. And that means, on a small range of motherboards, there is yet another BIOS setting to check for. That practice was soon discontinued, in favor of pure PWM control for four pin fan headers. Meaning that the providers of aftermarket coolers, should provide proper four pin fans, if they expected satisfied customers. When you buy a retail CPU now, from either Intel or AMD, you should expect to find a four pin fan packaged with the retail CPU. Paul
From: JD on 25 Oct 2009 00:14
Paul wrote: > JD wrote: >> Paul wrote: >>> JD wrote: >>>> I have a CPU fan that runs all the time at around 4,100 rpm. >>>> This is completely unnecessary when the weather is cool. I believe a >>>> speed >>>> of about 3,000 should be ok at present. >>>> >>>> Is there any such program around? I know about SpeedFan but I think >>>> it's a primitive piece of work. The CPU needs a delicate touch. >>>> >>>> I did a search and found >>>> http://wareseeker.com/free-cpu-fan-speed-control-software/ >>>> However it's hard to tell whether they are discussing the cpu speed >>>> or the fan speed. >>>> Anyone have experience of these? >>>> >>>> TIA >>> >>> Have you looked at your BIOS functions ? Maybe there is >>> an option in there to control the fan. >>> >>> Paul >> >> Great suggestion Paul. >> >> I looked in the BIOS and found 2 options for the fan >> Fan Control - [Enabled} >> Lowest Fan Speed - [Slow] >> >> The first one had no speed control as far as I could see and was the >> existing >> setting since the motherboard was installed >> I set it to the 2nd one and rebooted. >> It was exactly the same as before - whizzing along at 4,100 + or - a >> few hundred. >> >> I did have this fan plugged into the right socket - it is right >> beside the CPU. >> I looked in Control Panel - Add-remove hardware and it was no help. >> Likewise in the Control Panel itself. >> Do you know of any other possible location for a fan speed controller? >> >> TIA > > Maybe the next test, is to try Speedfan. If Speedfan cannot get any > response from the fan, then it could mean there simply isn't > a hardware feature there to control the speed with. (It could mean, > for example, that you've mixed incompatible components together. > Or that the motherboard makers are cheapskates.) > > The rest of this is some background. Mixing a three pin fan with > a four pin fan header, may deprive you of a control method. And > that is an example of how you can accidentally be stuck with > a screaming fan. > > ******* > > The CPU fan header has a couple features to control fan speed. > Back in the "three pin header" days, voltage control was used. > The fan normally runs from 12V. But the motherboard could control > the voltage, and deliver a variable voltage between 7V and 12V. > This would take a PWM output from the controller, and require a > MOSFET or transistor near the fan header, plus a capacitor, > to convert the pulse width modulated control signal, into > a voltage. It costs the motherboard maker some money to do that. > > X <--- RPM (from fan to motherboard, for monitoring) > X ---> 7 to 12V to power fan > X --- Ground > > If you're using Speedfan, Speedfan may find the registers that > control the PWM output. The register can be programmed, and > the hardware chip is then outputting a PWM signal. But if the > motherboard maker wants to save money, they don't bother to > install the interface circuit (the MOSFET and capacitor). Speedfan > cannot tell those components are missing. So one of the checks > I make, when someone has this problem, is to look at a picture > of the motherboard, and see if the appropriate looking components > are installed nearby. > > (Some general rules of thumb. Prebuilt systems from HP/Dell/Gateway > are the ones most likely to have fan control per header. Which > means they have the most fan control of all. On an Asus motherboard, > the cheapest boards have no fan control. A board with QFan has the > CPU fan controlled. A higher end board with QFan2, has two headers > under control, one via CPU temp, one via chassis temp. So that should > give some idea what to expect in terms of working channels. With the > four pin fan header generation, you're much more likely to have a > CPU fan control, so the situation should be getting slightly better > as time passes.) > > ******* > > The second control method, is of more recent design. Both > Intel and AMD now use four pin fan headers for CPU. The fourth pin > is (what a surprise) PWM. What is happening in this case, > is the responsibility for the MOSFET and capacitor, is now > up to the fan manufacturer, as they're inside the fan. The motherboard > has a fan controller interface on it somewhere (I can't say > right off hand, where this one is located now). The logic > signal output, running at perhaps 25KHz, is delivered on the > fourth wire of the fan. The fan runs at full 12V all the time. > The conversion circuit inside the fan hub, uses the pulse > width of the PWM signal, to control the voltage delivered > to the fan. That means the fan can run at 7V, using a > circuit inside the fan hub to make the 7V from the supplied > 12V. > > X ---> PWM (from motherboard to fan, 25KHz, indicates speed desired) > X <--- RPM (from fan to motherboard, for monitoring) > X ---> 12V DC (power from motherboard to fan) > X --- Ground > > So as a consequence of having that fourth wire and control > method, Intel recommends not attempting to reduce the 12V > fed to such a fan. That recommendation, is so the MOSFET > has sufficient signal applied, so it will be biased properly. > > Now, imagine what would happen, if you purchased an aftermarket > heatsink/fan combo, with a three pin connector, and connected > it to a four pin header. No PWM signal. No variable 12V. > And hence, no control method. Again, programs like Speedfan > will feel they're "dialing the knob", but nothing happens. > > ******* > > There is one other feature, which was used in the past with > Intel fans. They had a thermistor in the fan hub. If the > computer case air temperature rises, the fan is set to > spin faster, based on the measurements by the thermistor. > That feature does not lend itself to control by the user. > Its purpose is to compensate for the worse cooling situation > caused by hot case air. So if the computer has poor ventilation, > the CPU fan may scream a lot more than it would in a cooler > running case. Any other control method applied, multiplies > its effect, by the effect provided by the thermistor. So if > the computer case was very cool, the fan may hardly be > turning at all. > > Speed = Voltage_controlled_speed * thermistor_set_speed > > Anyway, my next steps would be some Speedfan testing, and > some visual inspection. Like, checking whether there is a > three pin fan connected to a four pin header. On an older > motherboard, whether the appropriate components are next > to the three pin headers, and so on. As far as I know, there > isn't a programmatic way of determining whether the controls > are actually hooked up and working. A program could certainly > observe the RPMs, and notice that nothing is happening, but > I'm not aware of any program bothering to carry out such an > analysis for the user. > > During the transition from three pin to four pin CPU fan > header, Asus made some motherboards with dual control > methods. The four pin header could be controlled as if > it was a three pin header. There was a BIOS setting, > that determined whether voltage control or PWM > control was used. And that means, on a small range of > motherboards, there is yet another BIOS setting to check > for. That practice was soon discontinued, in favor of > pure PWM control for four pin fan headers. Meaning > that the providers of aftermarket coolers, should > provide proper four pin fans, if they expected > satisfied customers. When you buy a retail CPU now, > from either Intel or AMD, you should expect to > find a four pin fan packaged with the retail CPU. > > Paul Thanks again Paul. I haven't read the above yet. Today I used the Intel Active Monitor and it has a window called Set Sensor Thresholds. There all the voltages can be allowed to vary a little e.g. 12V is set to vary from 13.2 to 10.8. Same for CPU core (+1.52V), set to go from 2.325 to 0.725. There is no variation for the processor fan. Back tomorrow :-) |