# [SOLVED] CPU Temperature; different programs, different readings



## SMRDcompany (Jul 2, 2009)

Hello,

I'm trying to see how hot my CPU runs, but so far it's been a retarded experience.

This bellow is all idle

HWmonitor shows about 45C but the cores are like 30C
Coretemp shows about 26C
Speedfan shows 5 different temperatures like Temp1 Temp2 Temp3 Temp4 Temp5

And it cannot decide how fast it runs too

CPU-Z shows 3.9ghz while Everest shows 3.6ghz (Everest also shows that it has only 2MB of cache while it really has 8)

Here are some pictures



















Most importantly, the bios says about 46C and 3.6ghz, which I assume is the most accurate of them all. BIOS can't tell me the individual temperature of each of the cores though.

It's an AMD FX-8150 on ASUS M5A97 PRO

Cheers


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## Tyree (May 10, 2009)

*Re: CPU Temperature; different programs, different readings*

The Bios is usually the most reliable source for Temps & Voltages.
Speedfan is for fans and rarely gives any accurate Temp or Voltage readings.


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## SMRDcompany (Jul 2, 2009)

*Re: CPU Temperature; different programs, different readings*

Thanks, HWmonitor seems to be spot on to BIOS readings with it's 46C, but what about the core temperatures it's reporting? The core temperatures of HWmonitor and coretemp are the same, so what reading is important to me, core temperatures or this "CPU" temperature my bios reads as well?


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## Wrench97 (May 10, 2008)

*Re: CPU Temperature; different programs, different readings*

The CPU temp is the sensor on the motherboard socket, the core temps the sensors on the cpu itself, the socket temp is normally warmer, for overcocking the core temps are the ones to watch.


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## SMRDcompany (Jul 2, 2009)

*Re: CPU Temperature; different programs, different readings*

Alright thanks, so you say that the socket temp will not increase as much as I overclock, so the main difference are core temps?


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## greenbrucelee (Apr 24, 2007)

*Re: CPU Temperature; different programs, different readings*

remember a cpu will run at slower speeds when not doing much and then run at full speed when needed unless you have the option switched off in the BIOS


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## Wrench97 (May 10, 2008)

*Re: CPU Temperature; different programs, different readings*

The socket temp will increase, but the individual core temps are what to look at as the socket will be more of an average temp. Single threaded programs will put more load on 1 core so while the average will rise once in a while you see just one core getting warm.


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## SMRDcompany (Jul 2, 2009)

*Re: CPU Temperature; different programs, different readings*



greenbrucelee said:


> remember a cpu will run at slower speeds when not doing much and then run at full speed when needed unless you have the option switched off in the BIOS


I actually disabled this stepping options in bios, but I've noticed a really interesting thing

When I'm loading applications, the CPU works at 3600 (not overclocked, factory values), but when it's idle, it's working at 3900...really strange

CPU-Z reports that when it's idle the CPU multiplier jumps from 18 to 19.5 creating this boost, what may cause this issue, or is this an incorrect reading on CPU-Z's part?


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## greenbrucelee (Apr 24, 2007)

*Re: CPU Temperature; different programs, different readings*

Do you have any auto overclocking features enabled in the BIOS?


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## SMRDcompany (Jul 2, 2009)

*Re: CPU Temperature; different programs, different readings*

No, it's not overclocked, bios is reporting 3600


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## greenbrucelee (Apr 24, 2007)

*Re: CPU Temperature; different programs, different readings*

Always believe the BIOS


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## gcavan (Aug 13, 2009)

*Re: CPU Temperature; different programs, different readings*



> When I'm loading applications, the CPU works at 3600 (not overclocked, factory values), but when it's idle, it's working at 3900...really strange


Not strange at all. Sound's like the processor is running exactly as designed. See AMD's Turbo Core Technology


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## SMRDcompany (Jul 2, 2009)

*Re: CPU Temperature; different programs, different readings*

Yeah, I had turbo technology off in BIOS, I just enabled it later and it's the same, I don't get how at idle it works at 3.9 and at full load it works at 3.6, I mean, what's the point? Or does CPU-Z not read the speed with turbo properly?


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## greenbrucelee (Apr 24, 2007)

*Re: CPU Temperature; different programs, different readings*

you could have faulty sensors.


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## Wrench97 (May 10, 2008)

*Re: CPU Temperature; different programs, different readings*

Turbo only works when the cores are lightly loaded, if you use all the cores turbo mode shuts down.


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## SMRDcompany (Jul 2, 2009)

*Re: CPU Temperature; different programs, different readings*

Wow good game AMD, I can really use that extra 300 MhZ when I'm doing nothing


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## Wrench97 (May 10, 2008)

*Re: CPU Temperature; different programs, different readings*

Intel works the same way.


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## SMRDcompany (Jul 2, 2009)

*Re: CPU Temperature; different programs, different readings*

Can you tell me any use at all for this feature? This sounds counterproductive as hell. It's like having a volume setting at 100% only for it to fall to 80% everytime you play any sound.


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## Wrench97 (May 10, 2008)

*Re: CPU Temperature; different programs, different readings*

If you are only loading 2 cores it's faster, but once you start to load up the third it slows to keep the heat in check. To me it seems like a nice feature on a laptop on a desktop it's a good marketing technique....................


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## SMRDcompany (Jul 2, 2009)

*Re: CPU Temperature; different programs, different readings*

Wait wait wait, the way AMD explained on it's FX 8xxx series it is that you get a boost to 3.9 when 8 cores are in use and when 4 are in use it goes to 4.2 .

I know that's what it says on the box itself too somewhere, or like on the website itself.


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## Wrench97 (May 10, 2008)

*Re: CPU Temperature; different programs, different readings*

There are some other conditions imposed also, I can't find the parameters on the AMD site and the rest are pretty sketchy.


> According to a slide recently published by Donanim Haber, this technology enables AMD's upcoming FX-Series processors to increase their operating speed by as much as 1GHz, when only half of the cores are active.


from AMD FX-Series Processors Can Turbo Up to 1GHz over Base Frequency - Softpedia

But temps and thread load do come into play.


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## greenbrucelee (Apr 24, 2007)

*Re: CPU Temperature; different programs, different readings*

Not many things use more than two cores, the less cores running the faster you can push the two cores with more than two cores running then multiplying the speed goes down.

I recently wrote on a thread about turbo boost with two cores running on an i7 turbo boost will boost in increments of 133MHz if all cores are running this will drop to 97 and even less.


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## SMRDcompany (Jul 2, 2009)

*Re: CPU Temperature; different programs, different readings*

Yeah but if half the amount of my cores are 4, why does it only activate when only 2 cores are in use?


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## greenbrucelee (Apr 24, 2007)

*Re: CPU Temperature; different programs, different readings*

thats down to the OS requesting the boost I would assume, it may not need it with more than two cores active.

Anyway cores are not important it's threads. The mpre threads you have the less something like turbo will be needed.


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## SMRDcompany (Jul 2, 2009)

*Re: CPU Temperature; different programs, different readings*

Alright thanks, I'll keep that in mind. I'll mark this as solved


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