Temperatures and Fanspeeds.

ex_forum_user_3

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Hi there,

There seems to be a lot of confusion as to why sensors give values and why Speedfan can't do anything with them.
Or why Everest give the wrong values.

The reason is simple, there are as many controller-chips and each chip has its own connections.
The only one that knows how they are connected is the manufacturer, as they decide how and what it connected.

Let me show you how it works, you can check the exact details in the below attached files.

The working is very simple:

1) To measure and control fan speed, all you have to do is connect the fan measuring wire to pin FANIN 1/2/3 and via the BIOS you control the speed IF it's connected via FANOUT 1/2/3
I know this is very simplistic, but it's the way it's done, there are a few extra components but that's basically all there is to it.
BUT, the connections and output regulation is done the way a manufacturer thinks is done best.
Typical MSI uses 1 fan control and 2 or 3 fan tachometer inputs.
So speedfan is able to control just the CPU-fan but not others (unless you see the BIOS can regulate more, then Speedfan can do it too!)
Ergo, always see what the BIOS can do, then you have a pretty good idea what is connected and what isn't.

2) Thermal sensors is a bit different, but all they do is measure a voltage-drop over a diode and calculate the temperature in the BIOS.
This is where a lot of people go wrong, most sensors will give a proper value, however Speedfan and Everest do not know what inputs are used!
They guess based on what is used mostly....so again, check in the BIOS yourself to have a good idea what sensors show what and how many are used.
Manufacturers typical do not use ALL connections the chip provides! Many are left open or have a shunt-resistor to prevent them from going wild, however, typical Speedfan and Everest show you a reading on such an input, they have to do that, as they don't know any better then there is something to read :bonk:
How could they? They didn't solder the connections.

So there you have it, what you are seeing in SpeedFan and Everest is merely a questionnaire of a Chip, they simply scan the addresses where they know the chip has readings, and if those readings are anything worth showing they will show it as give it a name.
Yes even the unused lines if there is anything to read, they DO NOT KNOW if it's a real reading or simply a resistor to close the input, yes that gives a reading to but is false.

As we say many times, DO NOT TRUST THOSE PROGRAMS TO BE TRUE, check the BIOS and correct the names/readings yourself, Speedfan as options for that.
These are not bad programs, far from it, but you have to adjust them yourself to match your motherboard...such matching can be done by check the BIOS for the readings, then you should be able to figure out what sensors are showing what readings.

If you still do not understand, then please stop using those programs, as you will never understand what you are reading, nor can you conclude anything from it.
Please read the PDF, as it's useful, even if you do not understand the schematics, there is a lot of calculation information.

Beware, this is only a sample of a chip that can be used, this sample is from the K8T Master 2FAR.

The boards I know from MSI all have the Winbondchip with a number like 83xxx:



That is the chip that you try to read, and if you know the chip you can find the information, heck you can even add your own censors if you find unused inputs :lol_anim:


 

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nt650_999

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At least in the case of Everest, I know that they will correct a temp that is off.  They use forums like this to work out issues; people can make requests in a public forum and Lavalys would respond, correct it and the end user would say thanks and be happy.  I don't know if they are as good as they used to be but we'll find out soon: I requested correction for the MSI FX790-GD70 "Northbridge" (=chipset) reading a couple days ago.

Speedfan is free and you get what you get and smile.  Everest you pay for, so it's right to expect more.  One way a vendor like Everest has to determine how temps should be done is they can tell a lot from their diagnostics, like this:

Sensor Type  Fintek F71889F + F75388SG (ISA 600h, SMBus 2Eh) 
  GPU Sensor Type  Diode (NV-Diode)

In any event, I agree that people should strive to work with the best information possible and not trust unsupported software without manufacturer accepted confirmation (or even supported software if the readings defy experience/logic).  Sometimes you have to act on second-best information because first best isn't available.  As long as you do so conservatively, you'll normally avoid doing anything too dumb or too expensive.


 

ismjoe

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Reference the postings regarding the above subject should a person presume that since Speedfan, HWmonitor, Everest, and others can't read the F71889F data properly that this implies that MSI Dual Core Center does not reflect correct information either? Does anyone know of a datasheet or chip pinout/spec sheet available for this super I/O chip? There isn't one available from Fintek, so how does MSI implement the chip on their MoBo's?
 

nt650_999

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See here: https://forum-en.msi.com/index.php?topic=135691.0

In short: Everest is working on it and MSI represents that the software they ship with their board, including AMD OD, reports correct temps.  The only temp dif between Everest and AMD OD is a northbridge temp difference that is 12C too high in Everest.
 

jrjr

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So, is tmpin2 in AOD the chipset?   :)
My remote 1 in speedfan is only 6-7 degrees or so higher than tmpin2 in AOD
 

joeguitar

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Mar 7, 2011
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I have a all-in-one 2280.when I turn it on this error is showed: "
system fan not found" what is problem?
 
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