wahjahka

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Oct 19, 2008
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cpu: core i7 920 @ stock speeds
cpu cooler: coolermaster v8
thermal paste: arctic silver 5

my idle temps are about 40C to 45C

seems a little high to me but i could be wrong, should i be concerned?!

i will post actual temps and prime95 temp results when i get home tonight.

and what does "Distance to TjMax mean?

i use RealTemp..

i will read the core i7 and core 2 temp guide after posting..maybe i should read before posting...!
 

SpidersWeb

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Temp guide is good :)
Idle temps aren't really important, and Intel's Tjunction (core temp) sensors are designed for overheating protection, not idle temp monitoring and often don't read under 45C or so. (So your CPU could be 35C for all we know).

Anywho, open RealTemp and watch the temps, then open up Prime95 and start a SmallFFT torture test, it'll take all of a couple of seconds to start seeing your highest load temps.

TjMax (from memory) is the maximum value the thermal diode can read. Usually it's 95 or 100C.
 

CompuTronix

Intel Master
Moderator
Guys,

Before this thread becomes a thermal train wreck, here's what you need to know:

Temperatures and overclocking are all about specifications, so it's very important to be specific. If we're not, then the topic makes about as much sense as comparing apples-to-oranges thermal fruit salad in a blender! :pt1cable: My objective is to assure that enthusiasts understand Intel's specifications, standards and test methods, so they can better decide how to apply and manage their overclocking options.

From Intel's Processor Spec Finder - http://processorfinder.intel.com/List.aspx?ParentRadio=All&ProcFam=3052&SearchKey=

All Core i7 9xx variants:

Vcore Max 1.375v
Tcase Max (CPU temperature) 68c
Tjunction (Core temperature) 73c

From the Core i7 and Core 2 Temperature Guide - http://www.tomshardware.com/forum/221745-29-sticky-core-core-temperature-guide


"Section 1: Introduction

Core i and Core 2 processors have 2 different types of temperature sensors; a CPU case (not computer case) Thermal Diode centered under the Cores, and Digital Thermal Sensors located on each Core. The case Thermal Diode measures Tcase (Temperature case), which is CPU temperature, and the Digital Thermal Sensors measure Tjunction (Temperature junction), which is Core temperature. Since these sensors measure 2 distinct thermal levels, there is a 5c temperature difference between them, which is Tcase to Tjunction Gradient. Core i7’s / i5’s and Core 2 Quad’s have 1 Tcase and 4 Tjunction sensors, while Core 2 Duo's have 1 Tcase and 2 Tjunction sensors ...

... The monitoring utilities provided by motherboard manufacturers monitor CPU temperature, while some popular freeware utilities monitor Core temperatures ... Real Temp ... is recommended for users interested in monitoring Core temperatures only ... SpeedFan monitors Tcase (CPU temperature) and Tjunction (Core temperature) ... "


The Thermal Specification shown in Intel's Processor Spec Finder is Tcase Max (CPU) not Tjunction (Core), which is a very common misconception among most enthusiasts. Since there's a 5c gradient between the CPU sensor and the Core sensors, (shown in the following Intel document) - http://arxiv.org/ftp/arxiv/papers/0709/0709.1861.pdf - just add 5c to the value shown in the Spec Finder to determine the corresponding Core temperature, which is 73c for all Core i7 9xx variants.

Intel's second and frequently misunderstood Thermal Specification, Tjunction Max, (100c for all Core i7 9xx variants) applies to overtemp protection such as Throttle and Shutdown, so you don't toast your transistors. As such, any i7 9xx Core temperatures which exceed 73c should be considered "overtemp". Further, when specifications are exceeded, then processor degradation becomes a concern, which is explained in the following AnandTech article - http://anandtech.com/cpuchipsets/intel/showdoc.aspx?i=3251&p=6

Prime95 Small FFT's is the Standard for processor thermal testing, because it's a steady-state 100% workload which yields steady-state temperatures, whereas Blend is a memory cyclic workload which yields fluctuating processor temperatures. Small FFT's will reach 97% thermal saturation within 7 to 8 minutes, so a 10 minute test is adequate. Thermal testing should be conducted as close as possible to 22c (72f) Standard ambient, with case covers removed, the computer clear of any desk enclosures, and all fans at 100% RPM to eliminate cooling variables, and to produce consistent and repeatable results for comparisons. If the Gradient between CPU temperature and "mean" (average) Core temperature is not ~ 5c, then BIOS is incorrectly coded. CPU temperature and Core temperatures can be individually calibrated in SpeedFan by following the Calibrations Section in the Temperature Guide.

OCCT and Burn Test (reminiscent of TAT) use LinPack, which shows thermal signatures that resemble the ups and downs of a bad day on the stock market, and cycle between light workloads, through test segments which spray all processor registers with all one's, (100% thermal load = 115% workload), and can push an overclocked i7 9xx with HT enabled at Vcore Max 1.375, right on past Tcase Max to ring the Tjunction Max bell like a fire alarm! :eek:

Since there are very few applications or games that will spike, let alone sustain processor workloads beyond 70% to 85%, utilities which load all registers with all one's are not representative of real-world computing. While these utilities are certainly very useful for stability testing, they are inappropriate for thermal testing. The 3DMark benches are excellent for stability testing, as are applications for ripping and encoding.

To make sense of CPU temperature and Core temperature, compare them to a 4 cylinder car with 5 temperature guages; 4 of the guages are cyclinder head temperatures (closest to the heat source), and the 5th guage is the overall engine temperature, which is 5c lower than the other guages, and is the temperature guage with which we're all familiar. We know the red zone (hot) for the i7 9xx starts at 68c (Tcase Max) on the engine temp guage and 73c (Tjunction) on the cylinder head temp guages, but if we push the engine too hard and peg all the guages, (95c Tcase overtemp / 100c Tjunction Max) then the engine will shut down.

If you'd like to learn more about processor temperatures, then just click on the link in my signature.

Hope this helps,

Comp :sol:
 

masterasia

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You are a CPU temp God. We should all adore you. I'm not being sarcastic.
 

CompuTronix

Intel Master
Moderator
masterasia,

Thanks for the vote of confidence, however, it's a serious uphill battle to help the community understand this mess, no thanks to Intel. I've been at this for nearly 3 years now, and the confusion and misconceptions I see in the Forums with n00bs and enthusiasts alike, simply amazes me. Considering the way in which Intel's Thermal Specifications are worded, it would confuse a thermodynamics lawyer! :pt1cable:

When I became involved in processor temperatures, there were plenty of Overclocking Guides, but not a single Temperature Guide to be found anywhere on the Internet, so I wrote the first one, which became a Sticky here at Tom's on 2/2/07. Since then, I've invested over 2,000 hours of research, hands-on testing, composition, editing and updates.

Most users find my Guide a difficult read, however, it's a complicated topic. I've searched for ways to simplify the information as much as possible, but if I put it in a "Temperatures for Dummies" format, the details are lost, and it almost raises more questions than it answers. To help answer questions for Forum Members, I sometimes re-post sections of the Guide, or type lengthy, time consuming explanations. Lately however, I've been re-posting the information you've quoted above.

In most instances, it seems to answer most questions, and brings the topic into perspective. If it's helped once again in this thread, then I'm pleased.

Comp :sol:
 

john_smarty

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Nov 22, 2008
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idle fixed my cable management up and installed a couple more fans and i am down to low 40's (idle) on stock cooling maxed out it gets around 62 (100 %load)