Core Temp Vs. Speed Fan - Which one is correct?

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karmusjc
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Core Temp Vs. Speed Fan - Which one is correct?

Post by karmusjc »

Hi,

I'm a long time user of the All CPU Meter gadget found at AddGadget.com which displays cpu usage and temps from a third party app. I recently downloaded their newest version of this gadget which uses Core Temp but the previous version used Speed Fan. After installing Core Temp and the new version of All CPU Meter, I was surprised to see that the temps displayed were 20°C higher than normal!!

So here's a screenshot with both apps side by side.

Image

My question is which one is right?

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The Coolest
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Re: Core Temp Vs. Speed Fan - Which one is correct?

Post by The Coolest »

The TjMax value, which is the reference point for temperature monitoring is not simple to detect on the Atom processor.
By specs, the TjMax is supposed to be 90C, but not all of the processors have such TjMax.
Core Temp takes it's best shot of guessing the TjMax correctly, but is not always right. For that reason Core Temp has temperature offset settings (Options menu).
Usually it's best to keep the processor at least 20C below the TjMax value while under heavy load. As long as you manage that, the "real" temperature is not important.

In your case, an offset of between -25 to -35 may be needed to give you correct and realistic temperature readings.
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AMD Ryzen 9 5950X (True Spirit 140 Direct) / Mobo: Asrock Fatal1ty X470 / EVO 970 500GB + WD Blue 250GB + HDD / GPU: Dell RX 570 4GB / Mem: 2x16GB DDR4-3200 G.Skill 32GTZKW TridentZ - 32GB total / PSU: Seasonic Prime Ultra Gold 650W
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Core i7 2600K 3.4GHz @ 4.3GHz (Scythe Mugen2) / Mobo: Biostar TP67XE / 2x Inland Pro 120GB + HDDs / GPU: ATi Mach64 VT2 / Mem: 4x4GB DDR3-1600 G.Skill 8GBXL RipJawsX - 16GB total / PSU: Seasonic S12II 620W.
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Xeon X3430 2.40GHz @ 3.06GHz or Core i3 540 3.06GHz @ 4.0GHz (Freezer 7 Pro) / Mobo: MSI H55M-ED55 / PNY CS1111 240GB / GPU: ATI FirePro V3800 / Mem: 4x2GB DDR3-1600 G.Skill 4GBRL RipJaws - 8GB total / PSU: Seasonic S12II 620W
AMD Phenom II X4 B93 / Mobo: ASUS M2A-VM / GPU: ATI Radeon Xpress X1250 / Crucial M4 120GB / Mem: 2x2GB DDR2-800 - 4GB total / PSU: Antec 380W.

Core Temp - Accurate temperature monitor for Intel's Core/Core 2 and AMD64 processors

marieke
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Re: Core Temp Vs. Speed Fan - Which one is correct?

Post by marieke »

Why does Core Temp report a temperature of 38°C where Speedfan reports 33°C ?
Both readings at same clock speed, mind you. Processor a bit overclocked and throttled.
If it just needs to read a Digital Sensor, which is so accurate ?
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Re: Core Temp Vs. Speed Fan - Which one is correct?

Post by The Coolest »

Both programs use the processor's integrated sensor, CPU temperature reported is basically affected by the TjMax value.
Core temp = TjMax - sensor value
In Core Temp the TjMax is 95c, in SpeedFan it must be set to 90, so the temps you see there are 5c lower.
Main rig:
AMD Ryzen 9 5950X (True Spirit 140 Direct) / Mobo: Asrock Fatal1ty X470 / EVO 970 500GB + WD Blue 250GB + HDD / GPU: Dell RX 570 4GB / Mem: 2x16GB DDR4-3200 G.Skill 32GTZKW TridentZ - 32GB total / PSU: Seasonic Prime Ultra Gold 650W
NAS:
Core i7 2600K 3.4GHz @ 4.3GHz (Scythe Mugen2) / Mobo: Biostar TP67XE / 2x Inland Pro 120GB + HDDs / GPU: ATi Mach64 VT2 / Mem: 4x4GB DDR3-1600 G.Skill 8GBXL RipJawsX - 16GB total / PSU: Seasonic S12II 620W.
Secondary rigs:
Core i3 7130U / MiniPC / SanDisk SDSSDP-128G / GPU: Intel HD 620 / Mem: 1x8GB DDR3L-1600
Xeon X3430 2.40GHz @ 3.06GHz or Core i3 540 3.06GHz @ 4.0GHz (Freezer 7 Pro) / Mobo: MSI H55M-ED55 / PNY CS1111 240GB / GPU: ATI FirePro V3800 / Mem: 4x2GB DDR3-1600 G.Skill 4GBRL RipJaws - 8GB total / PSU: Seasonic S12II 620W
AMD Phenom II X4 B93 / Mobo: ASUS M2A-VM / GPU: ATI Radeon Xpress X1250 / Crucial M4 120GB / Mem: 2x2GB DDR2-800 - 4GB total / PSU: Antec 380W.

Core Temp - Accurate temperature monitor for Intel's Core/Core 2 and AMD64 processors

marieke
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Re: Core Temp Vs. Speed Fan - Which one is correct?

Post by marieke »

so the TjMax is not fixed, provided by Intel, for every one to know ?
Or SpeedFan is not up to date on the data maybe.

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Re: Core Temp Vs. Speed Fan - Which one is correct?

Post by The Coolest »

Intel has posted pretty solid numbers for their 45nm series CPUs.
They have also posted TjMax values for 65nm processors, but most of them were simply giving impossible readings. So for the 65nm chips, TjMax is mostly a guess.
I don't know where SpeedFan gets their values, I get mine from trial and error.
Main rig:
AMD Ryzen 9 5950X (True Spirit 140 Direct) / Mobo: Asrock Fatal1ty X470 / EVO 970 500GB + WD Blue 250GB + HDD / GPU: Dell RX 570 4GB / Mem: 2x16GB DDR4-3200 G.Skill 32GTZKW TridentZ - 32GB total / PSU: Seasonic Prime Ultra Gold 650W
NAS:
Core i7 2600K 3.4GHz @ 4.3GHz (Scythe Mugen2) / Mobo: Biostar TP67XE / 2x Inland Pro 120GB + HDDs / GPU: ATi Mach64 VT2 / Mem: 4x4GB DDR3-1600 G.Skill 8GBXL RipJawsX - 16GB total / PSU: Seasonic S12II 620W.
Secondary rigs:
Core i3 7130U / MiniPC / SanDisk SDSSDP-128G / GPU: Intel HD 620 / Mem: 1x8GB DDR3L-1600
Xeon X3430 2.40GHz @ 3.06GHz or Core i3 540 3.06GHz @ 4.0GHz (Freezer 7 Pro) / Mobo: MSI H55M-ED55 / PNY CS1111 240GB / GPU: ATI FirePro V3800 / Mem: 4x2GB DDR3-1600 G.Skill 4GBRL RipJaws - 8GB total / PSU: Seasonic S12II 620W
AMD Phenom II X4 B93 / Mobo: ASUS M2A-VM / GPU: ATI Radeon Xpress X1250 / Crucial M4 120GB / Mem: 2x2GB DDR2-800 - 4GB total / PSU: Antec 380W.

Core Temp - Accurate temperature monitor for Intel's Core/Core 2 and AMD64 processors

mystere
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Re: Core Temp Vs. Speed Fan - Which one is correct?

Post by mystere »

hello, I also wanted an explanation on the difference in temperature indicated by these three programs.
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Re: Core Temp Vs. Speed Fan - Which one is correct?

Post by The Coolest »

It's explained in section #7 of the FAQ
http://www.alcpu.com/forums/viewtopic.php?f=63&t=892
Main rig:
AMD Ryzen 9 5950X (True Spirit 140 Direct) / Mobo: Asrock Fatal1ty X470 / EVO 970 500GB + WD Blue 250GB + HDD / GPU: Dell RX 570 4GB / Mem: 2x16GB DDR4-3200 G.Skill 32GTZKW TridentZ - 32GB total / PSU: Seasonic Prime Ultra Gold 650W
NAS:
Core i7 2600K 3.4GHz @ 4.3GHz (Scythe Mugen2) / Mobo: Biostar TP67XE / 2x Inland Pro 120GB + HDDs / GPU: ATi Mach64 VT2 / Mem: 4x4GB DDR3-1600 G.Skill 8GBXL RipJawsX - 16GB total / PSU: Seasonic S12II 620W.
Secondary rigs:
Core i3 7130U / MiniPC / SanDisk SDSSDP-128G / GPU: Intel HD 620 / Mem: 1x8GB DDR3L-1600
Xeon X3430 2.40GHz @ 3.06GHz or Core i3 540 3.06GHz @ 4.0GHz (Freezer 7 Pro) / Mobo: MSI H55M-ED55 / PNY CS1111 240GB / GPU: ATI FirePro V3800 / Mem: 4x2GB DDR3-1600 G.Skill 4GBRL RipJaws - 8GB total / PSU: Seasonic S12II 620W
AMD Phenom II X4 B93 / Mobo: ASUS M2A-VM / GPU: ATI Radeon Xpress X1250 / Crucial M4 120GB / Mem: 2x2GB DDR2-800 - 4GB total / PSU: Antec 380W.

Core Temp - Accurate temperature monitor for Intel's Core/Core 2 and AMD64 processors

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