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Need -a- ClueFlag for United States of America

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How can I eliminate a P4 Zeon's control over my cpu fan speed and have the fan ONLY respond to heat sensors?

I have a Dell 670 Workstation. It has a 3.60 Gig Zeon single processor. My problem is that the cpu fan speeds up and goes back down up to 10 times per minute. NOT super high speeds, but just enough to be EXTREMELY annoying when trying to concentrate on work. I read on Intel's site that the cpu acutally can control the fan speed. My fan uses four wires. NOT the standard four wire connector as found on the back of hard drives, but a very small flat connector. I would LOVE to be able to have the fan respond ONLY to ACTUAL cooling requirements and NOT when the processor has a one second burst in activity. Dell will NOT assist  beside replacing the fans and the motherboard. No change after these replacements. There is NO bios switch for changing this. I have a $5,500. computer that I cannot stand solely because of the constantly changing sound. Note: An associate has the exact same model of computer and her computer has the same exact fan problem. Not a defect but an annoying situation. I wish I could offer 1,000 points for this question, but I'm limited to the 500. Please note that I am NOT a "super tech" by any means. I'm hoping that an Intel expert will be able to assist me. In addition, when speaking to Intel regarding this, they would not continue the call when they found out it was a Dell computer. Oh well.....
Avatar of jhance
jhance

First of all, if this machine is under warranty you will likely void the warranty by changing or modifying the CPU heatsink/fan.  So if it is under warranty, I suggest you live with it.

You can certainly replace the stock motherboard controlled fan with an aftermarket one that is both quieter and runs at a constant speed.  The "throttling" action needs to come from the CPU since the heat sensor is on the chip and there is a driver that detects an increase in heat and throttles up the fan.  While I've not seen one that does this so often, the Xeon 3.6 GHz CPU is a POWER HOG and the difference between idling and full ultilzation could be very significant.

There are many aftermarket CPU heatsink/fan combos out there, many of which offer "QUIET" as a main selling feature.  These are usually made with much more heatsink material and much less fan so they are quiter by design.
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ASKER

I am happy to risk voiding the warranty to end up with a quiet machine. In addition, I would never install any modification that I honestly felt would in ANY way compromise the efficiency of the cooling system.

However, I was hoping that there were some sort of utility program that would over ride the signal that the fan is getting from CPU ACTIVITY and respond only to CPU HEAT. The way this is functioning now is that ANY INSTANTANEOUS increase in cpu activity will cause the fan to speed up. Even if only for 2 seconds! Two seconds of intense activity cannot cause the heatsink to show any increase in temperature. I feel that Intel made an error in firmware in that the action of the fan should be smoothed out considerably. This would have zero effect on the safety of the cpu.

I have not been able to locate a thermistor based fan solution for a Zeon processer yet. Zalman makes an incredible unit that is only compatible with a standard P4, not the Zeon. I'm NOT looking for total silence at all here. I ONLY want to eliminate the frequent CHANGE in fan speed. Any further thoughts?
Avatar of Callandor
Try running SpeedFan to control the fan speed based on temperature: http://www.almico.com/speedfan.php
I've tried speedfan and mobomonitor. Speedfan locks up my computer. Mobomonitor does not work. Also tried Fresh Devices diagnostic program to just SEE what the fan was doing rpm wise and it says it cannot find any cpu fan monitor points to interrogate.
It seems that this new fan works best when teamed with a motherboard that supports control in the BIOS: http://www.gamepc.com/labs/view_content.asp?id=x36o252&page=2  Do you have a setting in the BIOS that can be adjusted?
Hi Need-a-Clue :-)

Sorry to hear this is still a problem -- I remember discussing it before at:
https://www.experts-exchange.com/questions/21618473/Need-program-that-displays-cpu-fan-speed.html   I remember listening to your recordings -- and I agree that would be a real nuisiance => I'm surprised you've survived this long with it !!

If you want to do a little "surgery" you can probably control the speed yourself -- but you'll want to be sure and monitor the temps to ensure you have it set high enough to keep the CPU from overheating.   The wiring to the fan essentially has two functions:  (a) the voltage that controls the fan's rotation; and (b) a sensing input that lets the BIOS know the current rotational speed.

You could simply connect the fan to a molex connector (with an adapter), but the system would most likely refuse to boot because it would not be receiving a sensing input and would think the CPU fan was not rotating.  What you need to do is determine which of the pins are the voltage and which are the sensing input -- and connect the sensing input, but not the voltage lines.   Then connect the voltage lines through a fan speed controller (e.g. a Zalman FanMate or similar) to a molex power connection.   This will let you set the fan at a constant speed -- or if you use a thermally controlled fan controller with a separate temperature sensor you could even have it adjust automatically based on the actual temps.   A bit of surgery -- but it WILL work :-)
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Gary Case
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