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Which Temperature Reading is 'more' accurate?

Last response: in Overclocking
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February 28, 2007 10:11:39 PM

i've been going through the 'Core 2 Duo Temperature Guide' and testing my system with the temperature monitoring softwares, i don't get really the 'Tjunction (TAT and Core Temp) is Tcase + 15c = Tjunction'

idle = 41°C (Asus' PC ProbeII/speedfan) and 37/39°C (tat/core temp)
load = 57°C (Asus' PC ProbeII/speedfan) and 55/57°C (tat/core temp)

well i guess my question is, which one is more accurate?
so which 'rule' should i follow:

'(E) Tcase Load should not exceed ~ 55c.
(F) Tjunction Load should not exceed ~ 70c.'


System: all stock speeds/fans
cpu: e6600
mobo: asus p5b-e
ram: ocz pc6400
gfx: x1950xt
psu: cheap 450W
HD: 2x seagate 250gb in raid 0
Case: icute 0508 (lol, it has 12cm, 14cm, 25cm fan)
(http://www.overclockersclub.com/reviews/icute_case.php)
March 1, 2007 2:18:24 PM

I'd say your temps are on the high end but ok.
I'd go with the Tcase if that's your Q.
a b K Overclocking
March 1, 2007 3:43:12 PM

Will14, although your advice errs on the side of safety, it doesn't clarify the problem for patchez:

Quote:
...i don't get really the 'Tjunction (TAT and Core Temp) is Tcase + 15c = Tjunction'

idle = 41°C (Asus' PC ProbeII/speedfan) and 39°C (tat/core temp)
load = 57°C (Asus' PC ProbeII/speedfan) and 57°C (tat/core temp)

which one is more accurate?
so which 'rule' should i follow:

(E) Tcase Load should not exceed ~ 55c.
(F) Tjunction Load should not exceed ~ 70c.'

System: stock speeds/fans
cpu: e6600
mobo: asus p5b-e
Case: icute 0508 (12cm, 14cm, 25cm fan)


Variables

Ambient = ?????
Chipset = 965
C2D = E600
CPU Cooler = Stock
Frequency = 2.4 Ghz
Load = TAT 100%
Motherboard = Asus P5B-E
Vcore = Stock

patchez, you were very close to working out the answer for yourself. Your Tcase value is obviously too high for stock clock & Vcore. For your situation, the following items define the problem:

Parameters

(B) Tcase Idle should be ~ 2 to 15c higher than Ambient.

(D) Tjunction should be ~ 15c higher than Tcase.

The answer is that Tcase is offset by +15c due to incorrect firmware CPU thermal tables in BIOS. This type of offset is a common problem:

Quote:
Variables

The typical ~ 15c difference between the single Tcase temp, and the dual Tjunction temps can be erroneous due to calibration inaccuracies in chipsets, BIOS releases, driver versions, and motherboard utilities. Intel’s spec for thermal sensor accuracy is +/-1c, so temperatures can be quite accurate on hardware / firmware platforms free of manufacturer's deficiencies. Even false temperatures have offsets which can be analyzed, and when given correction factors, may still be reasonably accurate.


Corrected Temperatures:

idle = 26°C (Asus' PC ProbeII/speedfan) and 39°C (tat/core temp)
load = 41°C (Asus' PC ProbeII/speedfan) and 57°C (tat/core temp)

As you can see, your corrected temps now fit the Parameters, and Tcase + ~15c = Tjunction.

Hope this helps, and enjoy your rig! :D 

Comp 8)

Core 2 Duo Temperature Guide
Related resources
March 1, 2007 3:59:53 PM

^^ My new hero


:wink:
March 1, 2007 9:33:54 PM

thanx for clarifying CompuTronix, it was such a simple answer.
lol, i feel soo dumb now.
March 2, 2007 11:07:53 AM

Yeah I wasn't even sure what the question was, therefore had trouble answering it well =P
!