Can someone explain T Junction and my readings on this oc?

xringx

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May 2, 2007
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Here is my stuff and I have a question about TAT, core temp and speed fan




My specs
E6300 OC'd to 7x458 (3200) with a vcore of 1.2875 Lapped
Ultra 120 Extreme Lapped with a Scyth s flex


Chief tech case with 120mm fan in front, 80mm fan at side running at half speed for quiteness, 2 120mm fans for outtake, one in back one as a blow hole.



I am right now running Dual Prime 95's. Ambient temp is at least 76 degree in house, no more than 78 degrees ( have thermostat set at 76, but i am in a room that has 3 walls that is all windows...


Core temp says core 1=48c-50c
core 2=48c-50c


Tat says core 1=44c to 46c
core 2=44 to 46c


Speed fan pretty much agrees with core temp


Tat, core temp and speed fan all agree on idle, of 38-40c


My question, core temp when I set it to show tjunction, it shows 48c on idle and but when I start Dual Prime95's, it drops to 37-38c??????


Why?


now showing my tjunction at 35-37 on coretemp. TAT is 46-47 and speed fan is a solid 48c
 

Cooperstown39

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May 22, 2007
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There could be a number of things going on so I'll start with the easiest. In Core Temp, go to Options/Settings and look a the last check box "Show delta to Tjunction temp." If this box is checked then this is the problem. Assuming your Tjunction max. is 85c, and your delta to Tjunction is 35-37, then this would give you a temperature range of 48-50, which is in line with your TAT and speed fan temps.

The "delta to Tjunction" is reading directly from the MRS table and indicates how many degrees are left until the processor shuts down. CoreTemp assumes either an 85c or 100c Tjunction max. (shut down temp), depending on the processor stepping. Therefore, if the Tjunction max. is 85 and you have 35 left to hit that number then your temp is 50c (85-35=50).

You should also review an excellent guide from Computronix on this forum;
http://www.tomshardware.com/forum/221745-29-core-temperature-guide

It will guide you through a very thorough explanation as well as a calibration procedure for Speedfan.

Hope this helps
 

xringx

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That makes total sense... I didnt do any math to try to figure it out.

Yes, in core temp, Tjunction is set to 85c, and when I set it to show Tjunction, the number ad up to 85%

Your speedfan comment brings up a question. I have read that thread once, but didnt pay much attention.

Is it possible speedfan doesnt need calibration? because coretemp and speed fan agree with each other...


 

Cooperstown39

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May 22, 2007
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It is possible that you do not need to set an Offset in Speedfan. Unfortunately, the fact that Speedfan and CoreTemp agree only indicates they are reading from the same sensor, the sensor itself could still be inaccurate. The only way to know if an Offset is necessary is to actually go through the calibration process.

Computronix has recently updated the Temperature guide and the calibration process is explained in detail. If you haven't read this recently, it is worth reviewing again.

Hope this helps