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#1 - Idle temps are meaningless.


#2 - BIOS is roughly 50% load on the CPU (so it is odd that your idle is higher than your BIOS)

#3 - 60c is too hot for a heavily overclocked Core 2 Duo, regardless of where it is measured. There has been much talk about the C2D CPUs ability to go to 85c measured in TAT, but there has been no solid proof of where this number came from given. Intel states that the max rated tempeture for a C2D running at stock settings is 60.1C. It is highly unlikely that a difference of 25c exists between the IHS(where Intel's specifications are stated) and the core.

For a heavily overclocked Core 2 Duo you should not exceed 55c on the TAT program if you plan to keep the CPU for longer than a year.

If there is solid proof to support the claim of higher temps allowable, I encourge anyone to share that, but to date I have seen nothing that supports it.
 

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Quote:
Intel® Core™2 Duo Desktop Processor E6400:
Thermal Specification: 61.4°C

Quote:
Thermal Specification:
The thermal specification shown is the maximum case temperature at the maximum Thermal Design Power (TDP) value for that processor. It is measured at the geometric center on the topside of the processor integrated heat spreader. For processors without integrated heat spreaders such as mobile processors, the thermal specification is referred to as the junction temperature (Tj). The maximum junction temperature is defined by an activation of the processor Intel® Thermal Monitor. The Intel Thermal Monitor's automatic mode is used to indicate that the maximum TJ has been reached.
61.4C is the recommended MAX from Intel, for the temperature at "geometric center on the topside of the processor integrated heat spreader." The BIOS and other programs that DON'T read Core temps (TAT and Everest are not one of these), report this temperature.
 

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Doing some research on the temperature issue. For stock speeds, I have found this document:
http://download.intel.com/design/pro...s/31327802.pdf

Page 77: Thermal Profile (Intel® Core™ Duo Desktop Processor E6000 Sequence with 4 MB L2 Cache - Thus the E6600 & E6700).
Formula: Tc(MAX) = 0.26 x Power(W) + 43.2. Since the maximum specified power is 65W, Tc(MAX) = 0.26 x 65 + 43.2 = 60.1C. The cardinal question is now, how far this relationship between power and temperature can be extrapolated. Obviously, Intel is not going to specify anything beyond stock specs.

From same document, we see that the Tc(MAX) for the E6300 & E6400 is a little higher, as defined by Tc(MAX) = 0.28 x Power(W) + 43.2, thus 61.4C @ 65W power.

Finally, the Tc(MAX) for the X6800 is 0.23 x Power(W) + 43.2, and the X6800 has a max specified power of 75W, translating into a Tc(MAX) of 60.4C.

Again, this is all at stock Intel specifications. I will try to find how far the lineair relationship between power and Tc(MAX) can be extrapolated (if any) and if there is a definate answer to the question what the absolute safe Tc(MAX) is.

And indeed, these temperatures are defined at the geometric top center of the processor. TAT and Core Temp measure the individual cores, and thus spit out higher temperatures.
 

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Quote:

Originally Posted by Chozart
And indeed, these temperatures are defined at the geometric top center of the processor. TAT and Core Temp measure the individual cores, and thus spit out higher temperatures.

That's the million dollar question. If this is indeed correct, what would be the absolute highest TAT temp that one should use? I've been sticking to 60 @ load on small FFTs in Orthos. Some people say more, some say that one should stick below 55, and intel, who I e-mailled earlier this week said:

Quote:
Hello Jimmy2Shoe,

Thank you for contacting Intel(R) Technical Support.

I understand that you are seeking information regarding the operating temperature of the Intel(R) Core(TM) 2 Duo processor E6300.

The maximum operating temperature of the Intel(R) Core(TM) 2 Duo processor E6300 is 61.4 degrees Celsius. As long as the processor is operating under this temperature it is operating within specifications. We recommend setting any thermal alarms about three (3) degrees below the maximum recommended temperature for the processor. We do not have a normal operating temperature for the processor as this temperature will vary depending on the chassis and other hardware installed on the system as well as the actual load the software is placing on the processor.

To verify the thermal information for this processor please visit the following website:
http://processorfinder.intel.com/det...px?sSpec=SL9SA

For more information on thermal management you may visit:
http://www.intel.com/cd/channel/rese...eng/299986.htm

We also recommend using a thermally advantaged chassis. Please check the following website to identify a thermally advantaged chassis:
http://support.intel.com/support/pro.../CS-008537.htm

You can find a list of tested thermally advantaged chassis at the following website:
http://www.intel.com/cd/channel/rese.../eng/53211.htm

For more information on system overheating please visit the following website:
http://www.intel.com/cd/channel/rese...eng/242783.htm

We also recommend having the latest BIOS version for your motherboard.

I see that you are also looking for information on "overclocking".

Overclocking is neither recommended nor supported by Intel(R).
Information on this subject can be found at:

http://www.intel.com/support/process.../cs-007627.htm and
http://www.intel.com/support/process.../cs-001614.htm

Please do not hesitate to contact us again if you need further assistance.

Sincerely,

Adolfo S.
Intel(R) Technical Support

Intel(R) Processor Support Web Site:
http://support.intel.com/support/processors/index.htm

Intel is a registered trademark of Intel Corporation or its subsidiaries in the United States and other countries.

*Other names and brands may be claimed as the property of others.
 

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Quote:


Originally Posted by Chozart

And indeed, these temperatures are defined at the geometric top center of the processor. TAT and Core Temp measure the individual cores, and thus spit out higher temperatures.

Possibly, I have not tested Speedfan or Everest, and certainly no way for me to test any of the other manufacturer's programs on my ASUS board, but my readings from PC Probe and TAT are within the margin of error to be the same and indeed, many times do match exactly.

There also is little chance of a 25c difference in temperature from the center of the IHS to the cores on the inside. I had similar thoughts that there may be some varience, although my thoughts were closer to 10c or less varience. However, in another thread The Manual provided some insight and information that I found to be logical and supportable that confirms that there is no way an 85c max temp rating for these CPUs can be maintained....especially when overclocking them.

Which is why I urge caution. I may be wrong, or The Manual may be wrong, or anyone else may be wrong. The only difference is, if I am wrong, the blackened shell of a $500 CPU can not be laid on my shoulders. I only give advise that I would feel comfortable doing with my own equipment, and that can be supported.
 

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I wonder what the point is where those guys throttle.

sdumper probably knows...given his insane experiments on stock air (he had a E6700 at 71C IDLE!)

What I saw, the 85C is mentioned because Core Temp also works with other CPUs (merom), that have a much higher temperature tolerance.

Finally, what would be the difference between the design for the E6xxx series and the T5xxx/T7xxx (Core 2 Duo for mobile platform). The latter have a thermal spec of 100C(!)
http://processorfinder.intel.com/Lis...Spec=&OrdCode= (check the CPUs; all have a thermal spec of 100C)

As far I know, the design is fairly similar. Does that mean the desktop CPUs are overly conservatively spec'ed?

Enough stuff to speculate on... still trying to find a definate number from a reliable website (plenty of arguments in forums.. LOL)

At this moment, I am leaning toward the opinion that the E6xxx CPUs can take a good deal of heat, but I will not recommend (I have hinted in the past, for which I apologize) tems above 60C before anyone finds definate proof.
 

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Quote:


Originally Posted by Chozart

What I saw, the 85C is mentioned because Core Temp also works with other CPUs (merom), that have a much higher temperature tolerance.

Finally, what would be the difference between the design for the E6xxx series and the T5xxx/T7xxx (Core 2 Duo for mobile platform). The latter have a thermal spec of 100C(!)
http://processorfinder.intel.com/Lis...Spec=&OrdCode= (check the CPUs; all have a thermal spec of 100C)

As far I know, the design is fairly similar. Does that mean the desktop CPUs are overly conservatively spec'ed?

I know the mobile chips use the same basic architecture........but they must be manufactured differently as I doubt Intel would state different specifications if they were identical. Mobile CPUs are expected to take higher temps, and they generally cost much more than their similar desktop cousins.

That's my speculations. I have also had little luck in finding anything solid, only discussions on other forums stating the same things.
 

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Yeah...

I think sdumper is the only one who's gotten his Core 2 Duo to throttle, which seems indeed to happen in the 80C range. Since we always have preached to stay about 20 C or so below the throttling point (That's what the advised max temperature turned out to be, give or take), I am for now sticking with the 60C point as my limit.

If you're a bit more conservative, 55C might be a good advice.
 

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60c Prime 95 load, or 60c TAT load.

I load the same in Speedfan with TAT and Prime 95, but when TAT loads it, it usually reports around 60c, whereas Prime 95 load reports 53c in TAT.

And to be honest, I strongly think that the thermal specification was taken from temps reported from the IHS, which would be similar to the temps that Speedfan reports rather than TAT.

Imagine if prescotts had a TAT, people would be freakin out from insane CPU temps.
 

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Quote:


Originally Posted by kevsta112003

60c Prime 95 load, or 60c TAT load.

I load the same in Speedfan with TAT and Prime 95, but when TAT loads it, it usually reports around 60c, whereas Prime 95 load reports 53c in TAT.

And to be honest, I strongly think that the thermal specification was taken from temps reported from the IHS, which would be similar to the temps that Speedfan reports rather than TAT.

Imagine if prescotts had a TAT, people would be freakin out from insane CPU temps.

I also get two separate load temps in Prime95 and TAT.
TAT is usually up by like 5-6C from Dual Prime95 load, which makes me think that Dual Prime95 is not fully stressing a C2D.

I agree 100% with your 2nd and 3rd statements, exactly what I was thinking
.
 

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That is assuming a lot of things, mostly that the core is that much hotter than the IHS, which is what we are trying to verify.

Also, if the specs are given for the IHS (and they are, this is confirmed by Intel's site), and supposedly the 3rd party software reads from the board, under the CPU......then what are we to conclude from the fact that TAT and the other programs read very similarly most times?

You know what? I am going to do a little experiment this week, I don't know why I didn't think of this before.

I am going to place a thermal probe between my IHS and heatsink and then compare the temps it reports to the temps reported by TAT and PC Probe, and Speedfan.

This way we can "see" what the temp of the Core is compared to the temp of the IHS where the spec is given from.

I should be able to complete this by Monday or Tuesday as I have several projects going right now.
 

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Quote:


Originally Posted by Thumper

That is assuming a lot of things, mostly that the core is that much hotter than the IHS, which is what we are trying to verify.

Also, if the specs are given for the IHS (and they are, this is confirmed by Intel's site), and supposedly the 3rd party software reads from the board, under the CPU......then what are we to conclude from the fact that TAT and the other programs read very similarly most times?

You know what? I am going to do a little experiment this week, I don't know why I didn't think of this before.

I am going to place a thermal probe between my IHS and heatsink and then compare the temps it reports to the temps reported by TAT and PC Probe, and Speedfan.

This way we can "see" what the temp of the Core is compared to the temp of the IHS where the spec is given from.

I should be able to complete this by Monday or Tuesday as I have several projects going right now.

Sweet.
You should definitely start a new thread about it, ill be sure to bookmark it.
 

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Quote:


Originally Posted by kevsta112003

Sweet.
You should definitely start a new thread about it, ill be sure to bookmark it.

Me too. Looking forward to it
Speedfan, TAT and Everest are driving me crazy..
 
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