Intel TAT / CoreTemp / IDCC all different temperatures....

[Miwo]

Which do I trust? How can I find out which one is the most accurate? Crank up voltages + speeds until I start throttling at the 85C mark?

[gtj]

IDCC is reporting the thermal diode not the core temps and it looks correct in relation to TAT. Coretemp just looks wrong.

[eva2000]

coretemp is real temp

[NickS]

Really? Confirmed with a 3rd party temp sensor taped on to CPU core or something? I figured TAT would be the most accurate..

Just interested because you seem so sure, suprised me..

[Millyons]

mabey cause its a 4300?

although do they show that when only one by one are turned on.....some monitoring apps screw up when there are other monitoring apps on....

[Miwo]

Really? Confirmed with a 3rd party temp sensor taped on to CPU core or something? I figured TAT would be the most accurate..

Just interested because you seem so sure, suprised me..

hrmmm.....
well, i guess ill watch ThrottleWatch, and tone down my fan to try and get past 85C. If it throttles, ill know which one is accurate...

[NickS]

Wow, good idea! Just be careful

[Millyons]

Wow, good idea! Just be careful

i think TAT will throtle it when it sees 85 ish....

when c2d came out and before it became common knowledge that not all are the same concerning temperatures, cause of IHS and stuff i played with "overheating" mine quite a bit, i couldnt believe the temps and was also wondering when it will throtle and shut down....well i throtteled it 100 times and even let it shut down at 111c (asus probe) a few times and the chip is still running strong, they seem quite durable......oh ya in the end my chip just needed lapping......

but in case of this thread i think it might be some bug/incompatibility more than such high heat, its a 4300 allendale afterall

[Miwo]

Update....



Turned down my fan until I could barely hear it. Looks like Eva is right......or this Throttlewatch is broken >_<.......

[eva2000]

it's a known fact that IDCC reports the core2 cpu's legacy temp sensor versus Coretemp's digital sensors.... also TAT and throttlewatch probably hasn't been updated for E4300 and TAT was never meant for public release http://i4memory.com/showthread.php?t=3265

I've tested a few core2 cpus across alot of boards and coretemp is pretty consistent at my known 24/7 stable oc of 3600mhz at 1.37-1.43v vcore resulting in similar temps for coretemp. TAT/and board software all differ from board to board.

[Miwo]

lmao...so after that testing I just did there is a possibility that ThrottleWatch is broken for e4300, or a combination of all things being broken...

Eva, I will take your input on CoreTemp being the most accurate because it sure seems that way when I feel the temperature using my finger. When TAT reads 90C, the heatsink was warm/hot to the touch, but not so hot that I couldn't keep my finger on it

I will try one more test to try and eliminate Throttlewatch as a source of error, and that will be running a bench when my TAT temperature is over 85C. If my results are subpar then what they usually are, ill take that as throttling

[Millyons]

i think throttlewatch doesnt work with c2d anyway use rightmark RMClock, or just look at cpuz to see is the speed is lowered

[Miwo]

Last Update:



Eva is definitely 100% right on this. Processor hasnt throttled and I see no decrease in performance. Overall I must say that this was a nice good fun learning experience for me. Since I know CoreTemp is accurate, time for more OCing on my new E4300 with my sexy jam packed HTPC Desktop case on Air

[fgw]

thats what i have posted over in the abit aw9d-max forum to clear things up:

Case Temperature
intel thermal specs always references a case temperature (TC). this TC is defined as the temperature measured at the geometric center of the package on the surface of the IHS.

X6800 TC = 60,4C
C2D with 4MB L2 cache TC = 60,1C
C2D with 2MB L2 cache TC = 61,4C


PROCHOT#
the system bus signal PROCHOT# will go active when the processor temperature of either core exceeds its maximum operating temperature. this indicates the Thermal Control Circuit (TCC) has been activated. the temperature at which the PROCHOT# signal goes active is individually calibrated during manufacturing. once configured, the processor temperature at which the PROCHOT# signal is asserted is not re-configurable.


THERMTRIP#
the processor will automatically shut down when the silicon temperature has reached its operating limit. at this point the system bus signal THERMTRIP# goes active and power must be removed from the processor. the temperature where the THERMTRIP# signal goes active is individually calibrated during manufacturing. once configured, the temperature at which the THERMTRIP# signal is asserted is neither re-configurable nor accessible to the system.


Digital Thermal Sensor
the Digital Thermal Sensor (DTS) is the on-die sensor to be used for fan speed control (FSC). each core has its own DTS. the DTS is monitoring the same sensor that activates the TCC. readings from the DTS are relative to the activation of the TCC. the DTS value where TCC activation occurs is 0 (zero).


Core Temp
as far as i know, thats the point where core temp kicks in. core temp just reads two registers. the first one is the one which holds the temperature where TCC gets activated, the second one is the register holding the DTS value itself. all what core temp has to do, is subtract the DTS value from TCC activation temperatur to get current core temperatures. as i understand, core temp displays the TCC activation temperature as "Tjunction" and the actual temps of both cores under "Core #0" and "Core #1".


thats how i understand this after reading intel C2D processor specs, intel C2D thermal guidelines and core temp description ...

so, as long as TCC is not activated (the cpu is not throttling) temps are below the 85C core temps shows as "Tjunction". i guess throttling could also be seen within cpu-z as reduced clockrate. have not yet tested this, anybody seen this already?
in this case we safely can assume TAT is wrong. somebody mentioned already, TAT was not written for this processors. it is a tool designed to test mobile cpu's. as this temps are read from registers, it's likely TAT reads the wrong register ...

[alpha0ne]

After playing with my E4300 I too am reasonably sure that CoreTemp is NOT reading these chips correctly as I have stated in my E4300 quick test shown HERE

[The Coolest]

thats what i have posted over in the abit aw9d-max forum to clear things up:

Case Temperature
intel thermal specs always references a case temperature (TC). this TC is defined as the temperature measured at the geometric center of the package on the surface of the IHS.

X6800 TC = 60,4C
C2D with 4MB L2 cache TC = 60,1C
C2D with 2MB L2 cache TC = 61,4C


PROCHOT#
the system bus signal PROCHOT# will go active when the processor temperature of either core exceeds its maximum operating temperature. this indicates the Thermal Control Circuit (TCC) has been activated. the temperature at which the PROCHOT# signal goes active is individually calibrated during manufacturing. once configured, the processor temperature at which the PROCHOT# signal is asserted is not re-configurable.


THERMTRIP#
the processor will automatically shut down when the silicon temperature has reached its operating limit. at this point the system bus signal THERMTRIP# goes active and power must be removed from the processor. the temperature where the THERMTRIP# signal goes active is individually calibrated during manufacturing. once configured, the temperature at which the THERMTRIP# signal is asserted is neither re-configurable nor accessible to the system.


Digital Thermal Sensor
the Digital Thermal Sensor (DTS) is the on-die sensor to be used for fan speed control (FSC). each core has its own DTS. the DTS is monitoring the same sensor that activates the TCC. readings from the DTS are relative to the activation of the TCC. the DTS value where TCC activation occurs is 0 (zero).


Core Temp
as far as i know, thats the point where core temp kicks in. core temp just reads two registers. the first one is the one which holds the temperature where TCC gets activated, the second one is the register holding the DTS value itself. all what core temp has to do, is subtract the DTS value from TCC activation temperatur to get current core temperatures. as i understand, core temp displays the TCC activation temperature as "Tjunction" and the actual temps of both cores under "Core #0" and "Core #1".


thats how i understand this after reading intel C2D processor specs, intel C2D thermal guidelines and core temp description ...

so, as long as TCC is not activated (the cpu is not throttling) temps are below the 85C core temps shows as "Tjunction". i guess throttling could also be seen within cpu-z as reduced clockrate. have not yet tested this, anybody seen this already?
in this case we safely can assume TAT is wrong. somebody mentioned already, TAT was not written for this processors. it is a tool designed to test mobile cpu's. as this temps are read from registers, it's likely TAT reads the wrong register ...

You understand it correctly, and a nice explanation

From those screenshots, it seems that TAT has somehow come to the conclusion that the E4300 has a "Tjunction" of 100C, while Core Temp checks the MSR and gets the proper value, which is 85C.
It could be a result of the CPUID value of this stepping, its below 6F4 (the first public ES aka B0 rev)
So its possible that TAT automatically assigns 100C as Tjunction, without even checking the proper MSR.

[impar]

Greetings!

Nice thread!

I was also having trouble figuring out which reading software was correct in my E4300.

Speedfan, CoreTemp and TAT were all showing different temperatures.

[impar]

Greetings!

Enabled CPU TM Function and PECI in BIOS.

The E4300 is at 2,7Ghz, 1,35v.
Ambient temperature is 17-18&#186;C

In idle:
CoreTemp reports 12&#186;C+16&#186;C
Speedfan 9&#186;C
TAT 28&#186;C+30&#186;C

Its impossible that, using a Zalman 9700 as heatsink, the CPU is bellow ambient temperature.

[andylihaha]

Greetings!

Enabled CPU TM Function and PECI in BIOS.

The E4300 is at 2,7Ghz, 1,35v.
Ambient temperature is 17-18ºC

In idle:
CoreTemp reports 12ºC+16ºC
Speedfan 9ºC
TAT 28ºC+30ºC

Its impossible that, using a Zalman 9700 as heatsink, the CPU is bellow ambient temperature.

so from your results, TAT is more accurate than the others.
this makes things even more confusing now. So the accuracy is depended from board to board.

[impar]

Greetings!

so from your results, TAT is more accurate than the others.
this makes things even more confusing now.

Yep. I cant get myself to believe CoreTemps readings.
Currently, the ambient temperature is 15&#186;C and CoreTemp reads 13-16&#186;C.

So the accuracy is depended from board to board.

Motherboard is P5B-Deluxe with 0910 BIOS.

A similar thread turned up in OCForums:
http://www.ocforums.com/showthread.php?t=497920

Also, SpeedFan is definitely off. With PECI enabled it read 9&#186;C, with it disabled it read 22&#186;C, and after one minute of Orthos it reads 79&#186;C now, after I turned Orthos off 10 minutes ago.

Could Miwo had the throttling feature disabled when he performed the test?

PS
Another thread in another forum discussing the same issue:
http://www.hardforum.com/showthread.php?t=1151311

[Battle_Rattle]

Many experienced people are contradicting each other here and in other threads...

Is there any consensus clarity on what is the most accurate core temperature monitor? Say for a Conroe and a P5B-D? CoreTemp the most accurate?

As it stands ... my PC probe II, TAT, and CoreTemp beta 94 are markedly different... While I understand the rationale, I dont think the answer "trust monitor X because it shows the highest temperature" is a good answer.



I have a ES HSF coming (supposedly) and I need an answer...

[fgw]

Many experienced people are contradicting each other here and in other threads...

Is there any consensus clarity on what is the most accurate core temperature monitor? Say for a Conroe and a P5B-D? CoreTemp the most accurate?

As it stands ... my PC probe II, TAT, and CoreTemp beta 94 are markedly different... While I understand the rationale, I dont think the answer "trust monitor X because it shows the highest temperature" is a good answer.

unfortunately you are out of luck!

i have read a lot of documents and forums on this issue. to sum it up:
no matter what tool you are using, all this programs have to rely on sensors integrated within the cpu to measure temps. intel supplies two ways to measure temps:

• the old fashioned thermal diode, readable via PECI interface
• digital thermal sensor (dts, introduced with conroes), readable through registers

the problem is as follows:
the thermal diode let you read an absolute temperature BUT is not very accurate AND needs to be calibrated in order to show correct temps! programs using this method will show slightly different readings depending how accurate the program developer calibrates his software.

on the other hand, dts is very accurate. as intel is intended to use this sensor for fanspeed control, this sensor DOES NOT DELIVER ABSOLUTE TEMPERATURES! i gives a reading how far the core is away from the point the cpu starts to throttling. all programs using this accurate sensor have to calculate absolute temps by subtracting dts readings from the mentioned throttling activation temperature. to make things even worse, intel did not supply this temperature value in any register as far as we know yet. thus, software has to "assume" this temperature value and do the calculations.
you can figure out yourself the probability, the programmer hits the correct value just for your very own processor.
this temperature value is burnt into the processor at manufacturing and may vary from die to die.
as said before: as this temperature value is not readable via any register, you are out of luck!

in your situation, you can of course use any program (i would recommend coretemp) and compare readings from one situation to the other. e.g. when changing the fan you can see the change in temps. this change is very accurate. but it is impossible to compare temps between different processors even if they are of the same type ...

[tzitzos]

very interesting

take a look at the screen below

temp on asus p5b dlx with waterchiller ( liquid -3C)

i think that coretemp it's the most accurate also.

[Millyons]

I dont even care about temps, i just try to stay away from the throttling point by about 10c for myself and other than that i dont care if my temps are xx or xx ....... but core temp is the one that is comparable to other mobos and setups, you just cant compare asus probe to gigabytes whatever ... other software like speedfan, everest, mbm actualy only shouw what probe (in this case) would show.... o another note when i put in a quad cpu probe showed 1/2 temps

[cadaveca]

In RD600 cpu throtlles @ 85c via smartguardian. Shutdown temp set in bios also reads same temp. this is not the same temp that Coretemp displays(61c).

So, unless it's the bios @ fault on RD600, Coretemp is not reading correctly. I have same issue too, reading 19c idle in 25c ambient, using AIRCOOLING.

this being said, coretemp reports same temp across many different boards for same cpu, when voltages/cooling are the same. Although the temp may not be perfectly accurate, it's the best we got ATM.