Help sorting out the correct temp readings

[disposablehero]

Working with CoreTemp 0.95, SpeedFan 4.32, and TAT .0427, i get what i believe to be an idle Tjunction of 29.

Also at idle, SpeedFan has a Temp1 reading of 25, Temp2 reading of 32, and Temp3 reading of -128. If I understand the sticky guide correctly, one of these readings should be my Tc. Doing a little math, my Tc should be ~14 and i need to offset Temp1 by -11. Unfortunately, ~14 cant be correct unless the Tc/Tj difference IS NOT ALWAYS ~15, because my ambient is ~24. To sum up, thats a measured ambient of 24, measured idle Tjunction of 29, and a calculated Tcase somewhere in the middle (but not ~15 degrees lower than Tj).

Working the other way and starting with my ambient temp of 24, the Temp1 reading by SpeedFan could be my idle Tc. Doing some more math, my Tj should be ~40 and i need to offset Core 0 by +11. Unless of course, the Tc/Tj difference IS NOT ALWAYS ~15. To sum up, thats a measured ambient of 24, measured Tcase of 25, and calculated Tjunction somewhere above that (and an inaccurate TAT and CoreTemp reading).

I tend to lean towards a correctly measured Tj reading, seeing that all 3 (TAT, SpeedFan, and CoreTemp) have the same reading. So, is my scenario atypical in regards to the Tc/Tj ~15 degree difference and how much should i offset the Temp1 reading by to get a fairly accurate Tc?



To put it in the correct format, assuming an accurate Tj reading:

Tcase: ?
Tjunction: Idle 29 / Load 54

Ambient = 24c
Chipset = 650i
C2D = E6600
CPU Cooler = Stock Intel
Frequency = 2.4 Ghz
Load = TAT @ 100% 10 minutes
Motherboard = MSI P6N Platinum
Vcore = 1.312

 

[disposablehero]

anyone?

 

[aoe]

Yep - we seem to have similar problems.

I normally rely on Computronix to help in these situations

Anyway, from the basics I understand:

1. tCase should be ~15C lower than tJunction
2. tCase should not be below ambient
3. Any software can incorrectly report temps

That last one leaves us with few options, and it's almost impossible to confirm a single accurate reading without a thermal probe (which I am seriously considering buying).

So, with the data you present, an ambient of 24C should mean that your tCase at best will be 24C (same as ambient) and adding 15C should mean that tJunction should not be lower than 39C. However, temps may not be linear between idle and load.

I get the feeling there are some dodgy sensors around.

Wish I could be more help.

 

[darkwire]

I get the feeling there are some dodgy sensors around.

qft

 

[bh626pro]

Intel specs the digital sensor on each core to +/- 1C.

The way the mobo BIOS picks up those temps is in question. Try enabling PECI in the BIOS under CPU - if you have an Asus P5b board. You will see your CPU vary wildly.

Ideally, different motherboards should report the same TAT temps off the same chip, but that isn't always the case.

Brendan

 

[graysky]

Use RMClock for core temp