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Thread: Real Temp - New temp program for Intel Core processors

  1. #551
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    Uncle did you get my email?

  2. #552
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    Quote Originally Posted by naTTan View Post
    Uncle did you get my email?
    It's on my things to do list!

  3. #553
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    Lol, take u're time, i am in no rush. Just worried the email didn't reach you :P
    Thanks again for the help.

  4. #554
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    @unclewebb:

    Your comment about absolute temperatures is something everybody should learn to accept as *facts*.

    I am so tired of telling "noobs" in norwegian forum about why they should not worry about more or less dubios software "reading" sensors but rather use som common sense.

    The *only* way to measure temperatures are like you describe in the first (and later) posts about your session in the basement before designing/coding your genious little app.

    3DMarknn - 79506/96025/33499/25592

  5. #555
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    one of the best "all-in-all" articles/posts in regards to CPU temps and calibration i just found here:
    http://www.tomshardware.co.uk/forum/...perature-guide

    But i have a problem, this guy gives tips how to calibrate using TCase using speedfan. Assuming that TCase is (depending on cooling solution) about 4 C higher than ambient.

    Calibrating temps as he says i get pretty high temps - and here is the difference in what you said:
    You said to calibrate using least possible Vcore (like 0.8) and he said "in bios leave on auto"....which i think is wrong. Since "Auto" would give each individual CPU different vcore, right?

    So...what we need...really some "all-in-one" half-way accurate measurement of Difference Tcase --> Ambient at given Vcore. If we know its about 4 deg higher than ambient with high-end cooler (Ultra Extreme etc.) for a Q6600 at 0.8V this would already help a lot!
    That above quoted article is very thourough...but as said i think he's making the mistake to calibrate with Vcore->Auto, but i can see being Tcase about 4deg higher than ambient with the least posssible Vcore like 0.8-1.0 and everything else in bios at default.

    G.
    Last edited by flexy; 03-29-2008 at 04:23 PM.
    Q6600 g0 L741 1.4V@35xx-> 8x44x FSB - 5:6 333/800- 2x2gb OCZ XTC Plats@53x mhz - dfi lp X38 TR2, Ultra Xtreme 120 - W7 64Bit - NV GTX275 - Corsair 520 (blew up) -> Toughpower 750W

  6. #556
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    Quote Originally Posted by ~aoe~ View Post
    The colour zones should therefore still be relevant.

    I just like this idea as a concept, although this is a very simplistic design. Whether it's wise to use a constant value like '20C from tjmax = red' for processors with varying tjmax values is debatable. In fact, there may be the same level of discussion around these values as there are about the real tjmax values for each processor family
    well considering that all software programs reading the dts will report the same Distance to TJ max, (coretemp and realtemp) the colored graph could be the same at the point you choose to go from yellow to orange to red or whatever...

    both programs even though they show 70C temps or 80C temps at load are going to show the same 25C distance to tj max.

  7. #557
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    jaredpace: I agree that all software that properly reads Distance to TjMax will report the same number for the same processor. The problem is that a reading of 25 on my TjMax=85C E6400 is completely different than that same 25 reading when I'm using my E8400 with a TjMax=95C. From that I see more confusion developing, not less.

    Instead of more temperature information I think we actually need less. Once you're running stable there isn't much need to monitor core temperatures. The Intel Core processors do a great job of taking care of themselves.

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    unclewebb, i very, very much agree. We now hae half a dozen or more ways to measure temps...and i can see differences +/-10 deg which translates, very real, that i dont have the slightest clue what the temps actually ARE

    In the future i think i will solely focus on DT->TJmax since i have so many different values depending on calibration and program used.

    I also have a problem "understanding TCase, i was looking at that Intel Spec sheet http://download.intel.com/design/pro...s/31559205.pdf
    in particular.

    here, example 95W CPUs you see a chart giving Max TCase depending on the current Wattage/power draw of the CPU....so at max 95 Watts Tcase equals 72.
    For the same CPU Tcase equals 58 deg at 50W...and so on.
    So max. Tcase is not a fixed value but always in relation to the current Wattage, IF I UNDERSTAND THIS RIGHT.
    So i have a problem understanding what Max TCase actually means...and also if it would apply for overclocked CPUS....say according to CPU wattage calculator i clock my CPU 3600 Mhz at 1.44 which equals 197W.

    If i would expand this chart (assuming it would go on in a linear way!) i would come to max Tcase at 197 W equals 97 deg.

    There must be a misunderstanding about the meaning of "max Tcase" since for the SAME CPU, how can max Tcase be LOWER with lower Wattage/Power Draw...so max TCase certainly canot indicate a safe max temp if its variable? Rather something like "expected" TCase temp at this and this wattage? <--- guessing...
    Last edited by flexy; 03-30-2008 at 05:01 AM.
    Q6600 g0 L741 1.4V@35xx-> 8x44x FSB - 5:6 333/800- 2x2gb OCZ XTC Plats@53x mhz - dfi lp X38 TR2, Ultra Xtreme 120 - W7 64Bit - NV GTX275 - Corsair 520 (blew up) -> Toughpower 750W

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    i actually *do* think we have a pretty good dilemma here, something which deserves way more attention and people like unclewebb with programs like realtemp.

    For example: If i use the new OCCT and use the internal temp measuring, which is the same temp as coretemp shows:

    I do some Prime/OCCT testing and quickly get 70-71 temp on two of my cores. If i leave OCCT at default it would already complain "CPU too hot!"...which just doesnt sound right since with 70C/core i STILL have 30 degrees to go according to "Distance to TJMaxx".

    So...either the CPU is "too hot"... (70/71 degrees)...or i still have *plenty* headroom with 30 degrees far from TJMax/Throttinling temp...so which one is right?
    We know that the only "real" information we have is "Distance to TJMax", thats what the sensors say. Ergo, the current 70/71 core as coretemp/OCCT shows and warns "it's already too hot!" sounds like total nonsense to me.

    We also can assume that Intel specced TJmax relatively relaxed and below extremely dangerous temp, Intel for sure doesnt have an interest in people RMAing one CPU after the other because the throtteling would happen already at very extreme temperature. It would defy the whole idea.
    I am really thinking about writing a small app showing a bar or something according to DT->Tjmaxx and ignore whatever other programs say in regards to temps.
    Last edited by flexy; 03-30-2008 at 06:50 AM.
    Q6600 g0 L741 1.4V@35xx-> 8x44x FSB - 5:6 333/800- 2x2gb OCZ XTC Plats@53x mhz - dfi lp X38 TR2, Ultra Xtreme 120 - W7 64Bit - NV GTX275 - Corsair 520 (blew up) -> Toughpower 750W

  10. #560
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    Quote Originally Posted by flexy View Post
    unclewebb, i very, very much agree. We now hae half a dozen or more ways to measure temps...and i can see differences +/-10 deg which translates, very real, that i dont have the slightest clue what the temps actually ARE

    In the future i think i will solely focus on DT->TJmax since i have so many different values depending on calibration and program used.

    I also have a problem "understanding TCase, i was looking at that Intel Spec sheet http://download.intel.com/design/pro...s/31559205.pdf
    in particular.

    here, example 95W CPUs you see a chart giving Max TCase depending on the current Wattage/power draw of the CPU....so at max 95 Watts Tcase equals 72.
    For the same CPU Tcase equals 58 deg at 50W...and so on.
    So max. Tcase is not a fixed value but always in relation to the current Wattage, IF I UNDERSTAND THIS RIGHT.
    So i have a problem understanding what Max TCase actually means...and also if it would apply for overclocked CPUS....say according to CPU wattage calculator i clock my CPU 3600 Mhz at 1.44 which equals 197W.

    If i would expand this chart (assuming it would go on in a linear way!) i would come to max Tcase at 197 W equals 97 deg.

    There must be a misunderstanding about the meaning of "max Tcase" since for the SAME CPU, how can max Tcase be LOWER with lower Wattage/Power Draw...so max TCase certainly canot indicate a safe max temp if its variable? Rather something like "expected" TCase temp at this and this wattage? <--- guessing...
    http://64.233.167.104/search?q=cache...nk&cd=20&gl=us
    read slides (espec. 10-17 and 11 and 14 in particular) its from a senior intel engineer, it is a partial explanation, not a full one though. There was another place that had more info, but I have too many links to look through, dont remember which one...I will post it if i can find it....assuming I saved that one.

    Edit: What is interesting is if we could find the exact thermal resistance (intel knows it) you could calculate tjmax from their formula.

    Tjmax C = Tcasemax C + (thermal resistance from tj to tcase C/W x TDP max W)
    this is specified in many intel and other white papers, cant find the one I got attached pic from...yet.

    Interestingly if take my E6850 and fill in numbers, you get
    tjmax = 72C + (.38c/w*65W) = 96.7C, c/w figure based on intel specs for each, though using c-a instead of j-t, I believe since cooling solution is what drives the tcase figure, it may be relevant to use such, also adding up other quoted resistances gets you close to this figure...though it will vary from part to part, dont believe it is huge variance.
    but add in the testing that is done with ? individual/batch corrections such as here http://www.yeongyang.com/report/RPG-...516-05)RPG.pdf ...and could be either still.

    E6x50 and E6540 with 4mb L2 and CPUID ending in 6FB
    tjmax = 72C + (.38c/w*65W = 96.7C

    And For E4000 series with CPUID ending in 6FD or 6FB (CPUID read by coretemp)
    tjmax = 73.3 + (.38x65) = 98C

    For E4000, E6000 series with CPUID ending in 6F2 or 6F6
    tjmax = 61.4 + (.38x65) = 86.1C

    E6000 CPUID 6f6 and 4mb L2
    tjmax = 60.1 + (.38x65) = 84.8C

    E8400
    tjmax = 72 + (.38x65) = 96.7C

    Also given Go stepping q6600 are 95W TDP, cpuid 6FB, with tcase max 71,
    and B stepping q6600 are 105W TDP, cpuid 6F7, with tcase max 62.2,
    than B stepping tjmax is 11C lower than GO, which is why those with B stepping complain they run ridiculously hot, if subtract 11C from tjmax on B stepping, temps on B stepping would make more sense, ie 11C lower.

    Unclewebb can you confirm your CPUID, I am betting you tested a 6F2 or 6F6 (if E4000 or E6000), and Gigabyte has 6FD or 6FB for his E4000. I can not be 100% sure of c/w, but I am pretty sure there is at least a ~12C difference in tjmax between those two cpuid, even though both e4000 series.
    Attached Images Attached Images
    Last edited by rge; 03-30-2008 at 04:46 PM.

  11. #561
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    Quote Originally Posted by unclewebb View Post

    Instead of more temperature information I think we actually need less. Once you're running stable there isn't much need to monitor core temperatures. The Intel Core processors do a great job of taking care of themselves.
    exactly the point. your software is a milestone and everyone is grateful for you making it for us. even if RT or CT is correct, and no-one including RGE knows the exact TJmax to find out for sure, the D to Tjmax is the only real relative value at hand. As for 6400/4xxx/8xxx having different thresholds, I'm sure that is all programmable into a self-adjusting graph once the program recognizes the cpu string. I applaud your program, yet am only expressing my concerns for what is needed next. People seem to agree.

    I think this is a definite way to show "less temperature information"

  12. #562
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    also if you have 25C distance to tjmax on an e6400 and the same 25C distance to tjmax on an e8400, are you saying that the headroom varies for either chip in that situation?

    Is it because the higher 95C tjmax yields a greater range for temperature activity or just because it is produced at 45nm?

    If the 6400 idles stock at 35C and the e8400 idles stock at 35C, I could see how there would be a difference. However this difference is programmable or adjustable with a ratio im sure.

    if the e6400 at stock 35C temps can goto 85C tjmax, then it has a 50C temperature range to allow for overclocked load speeds. Likewise, the e8400 at stock 35C temps which has a 95C tjmax or 105C tjmax, either has 60C or 70C of temperature range headroom to achieve your overclocked load speed.

    a data set per graph made specifically for each generation would show the same graphical output giving the user the same idea. It would definitely start an end to all the noobish "i see 58C here but 68C there which is right how much more can I oc??" bullcrap.

  13. #563
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    Quote Originally Posted by ~aoe~ View Post
    It seems clear that Intel are reluctant to release the tjmax values for their processors, and whilst it's possible to perform many measurements and come up with proposals for the tjmax values, we can never be certain that these proposals are correct, especially considering that:
    - the accuracy to which the sensors have been calibrated is not known
    - it's not possible to position external sensors to measure temps at the same point
    Quote Originally Posted by jaredpace
    ...and no-one including RGE knows the exact TJmax to find out for sure,..
    The values are fully known around given by Intel Senior Engineers. They're just NDA material that's all.

    I'll post as soon as I can get on the drive with data saved on it. Not been back to flat in 9 days yet all my gear is there and this is someone elses.

    As for DTS feedbacks ignoring TjMax; then true, they have to be accurate in the first place to judge off them. They were fudged on the new 45nm lineup for too many around, hence why the mobile 45nm were all reluctantly delayed till C1 step (google) to just fix this error, but they worked perfectly fine on the vast majority of 65nm SKU lineups.

    These are working stock E8400 DTS, just like the confirmed ES samples: http://www.xtremesystems.org/forums/...&postcount=138
    Very close full load temps, ambient, speed, voltage, difference is only cooler: TT120 vs. Xigmatek S1283 there.

    Keep in mind, from 65nm to 45nm, judging off just process node alone you are supposed to get 20-30% increase in circuit density and power density, 30% improvement in active power consumption, same for leakage power and just going off the surface area, you have a decrease in chip surface area to dissipate heat. Heat dissipation depends majorly on contact surface area and you now have 214/107 sq.mm of 130/65W compared to 286/143 sq.mm for 130/95/65W before. Electrical stability depends on heat density too, W/mm˛ and the new 65W@45nm have a heat density of 0.607 W/mm˛ compared to 0.455 W/mm˛ for 65W@65nm, hence why they have a lower voltage and heat threshold for stability and integrity and will require better cooling at the same wattage since you have less surface area yet more heat cramped into it. This is why you can't compare relative temperatures between both nodes.

    rge I read Intel ignored and deleted your query but some of your questions were pushing the boundaries too much for them to reveal without NDA through a SFAE. If you want answers, contact your local distributor and go through them to contact with an S.FAE. The only details you really require are already known though. I have the details for a while now and how to retrieve them, just wait a few.
    Last edited by KTE; 03-30-2008 at 02:24 PM.

  14. #564
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    well if you know for sure, you should probably tell unclewebb. duh

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    Preliminary results are just in. TjMax=95C is looking correct for my GO Q6600. It's heating up a lot quicker than a dual core when I pull the heatsink off but I think I should be able to get some camera screen shots like in previous testing. Details to follow.


  16. #566
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    I have a pile of pictures from 50C to 75C that look a lot like the following two where RealTemp is tracking the IR gun pretty closely.





    The picture in my previous post shows core0 and core1 tracking each other closely while core2 reports an idle temp 3C cooler. Perfect motivation for individual idle calibration for Quad cores.

    I tried to move the IR thermometer a little left of center when testing to hopefully be over top of Core0 and 1 but this is far from an exact science. I'll be exchanging the camera for a small high speed fan tomorrow so I can do some more testing without the worry of controlling a fresh quad without a heatsink on it. The heatsink isn't attached at the moment so I can remove it, take some temps and then throw it back on to keep things from getting too out of control.

    The difference in TjMax between RealTemp and CoreTemp is only 5C so it's not worth getting into an argument about test methods, theories etc. So far I don't see any evidence that warrants an increase in TjMax to 100C so I'll be leaving it at 95C. It will be interesting to see what my idle temps are with a HSF on it compared to room temperature.

  17. #567
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    Quote Originally Posted by jaredpace View Post
    well if you know for sure, you should probably tell unclewebb. duh
    The post above yours read:
    Quote Originally Posted by KTE
    I'll post as soon as I can get on the drive with data saved on it. Not been back to flat in 9 days yet all my gear is there and this is someone elses.


    So communication with our contact went as following. It's non-verbatim, I have to protect confidentiality but it's very close to the exact words said. Hope I don't get in trouble for this.

    KTE: I need a favor from you. Have you seen this thread? Common users don't have enough information on temps. and so we're guessing based on some unprofessional and limited testing and docs. You confirmed E8400 temps at 51C load earlier when you came in January but what about how we can work out temps? I know the 0x19C MSR but word has it that no one knows the correct TjMax and we're all guessing... why won't you release these details?

    Contact: Hmm.. were'd you hear that? AFAIK all developers who inquired know.

    KTE: I talk to most oc software developers regular, which ones are you talking about so I can confirm?

    Contact: We released this info back in 2006 and since then at every stepping update but you know it's only allowed under NDA in the BIOS writers guide. Ask Rudolf who made the Lm-sensors driver for Linux, or Matthias who develops CPUTempWatch or Fiery at EVEREST, Franck at HWMonitor, or Arthur who makes CoreTemp just to name a few, they all should know the details as they use them in their software calcs.

    KTE: I'll definitely ask them but why was this info never public?

    Contact: Check.. or if that's not enough, then

    KTE: Hmm.. damn I searched everywhere but you knew what to search for and I didn't. These guys knew it all along
    So.. let me get this straight: retrieve MSR 0xEE, bit:30 0=100 1=85 on earliest, for my Q6600 G0 its 0=100 1=85 and thats factory set TjMax?

    Contact: Spot on Tye

    ============2 days ago again============

    KTE: Just seen you're on, quickly, some more temp. qs for you.
    So you're saying devs know the info you gave me about MSR 0xEE to get TjMax for a Core 2 CPU plus even the latest TjMax updates for Penryn?

    Contact: Yep just check their software and they'll have all the updates to them from official authorised documentation for our Penryn 45nm lineup.

    Contact: Oh look

    KTE: 0=105 1=95 Penryn.. hmm, that makes sense, that's why most of them were in sync I guess. Thanks [names contact], you've been big help many times now!
    BTW what's the temperature Abit EQ/Gigabyte EasyTune and EVEREST "CPU" reports then? Sorry had to ask that its confusing me, it's lower than DTS...

    Contact: Probably Tcase, there's an analogue Tcase sensor there as well as the DTS sensors in each core, which motherboards can read and EVEREST probably reads that temperature. There is nothing else that will give a CPU temperature value but you're best off asking Fiery at their forum

    KTE: Ah ok. That sorta brushes things up.
    Can I get quick peak access to the guide?

    Contact: [names my uncle] can, just need to sign the NDA that's all

    KTE: No thanks

    KTE: Just reading link you gave... Fiery mentions any problems with the TjM/Temps and it's your fault

    Contact: Hehe, well someones got to take the blame. Temperatures shouldn't matter too much under normal warrantied conditions though
    Kinda makes things clear as crystal there. So, if you want to follow Intel like you do for MSR 0x19C, then check MSR 0xEE and you can go on from there combining the two.

    7 software temp. values compared on my Q6600 G0:



    Hope it helps, sorry for delay but I'm heavily backlogged on more than 180 PMs at just XS, many emails and many threads.

  18. #568
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    "Use of bit 30 in MSR 0EEh is *not* valid for desktop, workstation or server processors based on the Intel(R) Core(TM) microarchitecture. However, for mobile processors, this assumption *is* valid."

    Intel does not have any MSR that exposes the trip point for the TCC in the Core microarchitecture.

    Lexi S.
    Intel(R) Software Network Support
    ----------------------------------

    Someone at Intel is not being 100&#37; honest. The original thread at Intel where this was posted has been removed but this quote comes from a page on XS:

    http://www.xtremesystems.org/forums/.../t-136804.html

    Lexi checked with the engineers and went back and forth discussing this issue for 3 pages and the above quotes come from his last post before locking the thread.

    This has always been the problem. Software is reading this bit and assuming TjMax based on this bit but I agree with Lexi. S that this bit is not valid.

    Time to play musical processors. The latest version of OCCT assumes TjMax=100C for my E2160 which in my testing is definitely wrong. I'll have to throw it in and check MSR 0xEE.

    By using a high speed hand held fan I was able to do some more testing on my Q6600. With this method I have no problem maintaining a core temperature anywhere between 50C and 60C while taking IR readings. I had plenty of time for things to stabilize and at every point, RealTemp with TjMax=95C was exactly equal to the IR thermometer.

    Edit: Just re-installed the E8400 and sure enough bit30 if MSR 0xEE is not set so Everest and CoreTemp and other programs are assuming that TjMax=105C. For better or worse, RealTemp is based on real IR thermometer testing and I will continue to disagree with using any information from MSR 0xEE to determine TjMax for the desktop core processors.

    Last edited by unclewebb; 03-31-2008 at 09:13 AM.

  19. #569
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    Quote Originally Posted by KTE View Post
    Kinda makes things clear as crystal there. So, if you want to follow Intel like you do for MSR 0x19C, then check MSR 0xEE and you can go on from there combining the two.
    Thanks for the info, but several questions/problems. Btw...first let me preface this by saying I am not just being argumentative, and I think you, unclewebb, I and anyone else posting on this subject are simply after the truth, nothing more, nothing less, so I commend anyone's input, especially those with contacts. But with that in mind...

    1) If coretemp, everest, etc authors are all in "the know", then the tjmax of unclewebbs 1st cpu as 85 validates his method of measuring 85 with IR gun when DTS=0 and that the gradient from core to casing is less than 1-2c under those conditions,. Since intel white papers say resistance is even less for smaller dies like 45nm, ie E8400, and both coretemp and everest say tjmax is 105, how can you explain that under similar conditions when DTS=0, casing temps measure 95C, ie 10C lower? Either the resistance of E8400 casing would have to be much higher which contradicts intel papers, or resting power under similar conditions would have to be much higher for E8400...tj=tcase + theta(j-c)xTDP, given similar ambients, 10C difference is hard to explain.

    2) If tjmax of my E8400 is 105, as coretemp and everest report, and the cpu temp is diode temp, then that is saying the gradient from core to diode of 15C running orthos is accurate on my cpu as well as on others which are similar. However when I load one core, the gradient from die to die is only 1C. Not only is that seemingly impossible to be 1C from die to die, but be 15C from die to between dies, but it directly contradicts the die to diode gradient in this paper in figure 5 http://arxiv.org/ftp/arxiv/papers/0709/0709.1861.pdf, and directly contradicts intels white papers stating this gradient has decreased with smaller die's, and directly contradicts statement on intel slide presentation by intel engineer that this gradient is smaller on smaller dies, and directly contradicts realtime measurements. Note that tdiode is still between cores and on opposite side of TIM1 and IHS as Tcase measured.

    3) If that information on tjmax was released, why do the developers, such as coretemp author post on intel forums, asking for such information, and then a long argument ensues regarding he cant get NDA, because he is not a company....and there are recent arguments?

    4) In one of your links above this statement is provided by a software person on intel forum
    "It is true, some are calibrated to 100C, some are calibrated to 85C. We should call that value as Tjmax for Conroe/Woodcrest/Clovertown instead of Tjunction...
    It is correct, the Tjmax value, whether it is 85C or 100C, can be read from MSR 0xEE. This (85C or 100C) should be documented in the processor spec."

    We have all seen that and discussed before, it was NOT written by an intel engineer but one of software people, who repeatedly state they do not know the answers and always ask the engineers. Later on in that same thread, page 2, which is now suspiciously locked to viewing, an intel engineer who was introduced by intel as knowledgeable on the subject stated, "from intel specifically from one of our internal contacts for the processor documentation", that states,
    "Note Tj is not a fixed value and the IA32_TEMPERATURE_TARGET[15:8] value can vary from part to part. Tj is also not software readable."

    Also in direct response to Rudolphs question "Perhaps put 100 as TjMax and write to documentation that it is safe until you reach 100? (and also that this temp is artificial) Do you think users might benefit from MSR_TARGET_TEMP too?"
    Intels answer "No."

    That leads one to believe the first post was from a confused intel software person, who was dispensing information from mobile cpus, not deskstops. Either that or the second engineer who was introduced as someone who knows, was lying, which I doubt.

    I would be happy if intel did let us calculate absolute temps, but for me it is not anywhere near crystal clear...yet.

  20. #570
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    The DTS reports an offset to "throttle", which is a "hardware set" value(resistance) within the pcb/core of a CPU (if I have understood some threads correctly).
    This is a relative temp, not a "real" temp.
    The author of realtemp have tried to do some "reverse engeneering" to find the actual temps.
    If we assume that all CPU's (chips) are equally processed on a wafer.
    That there is no margin of errors in the "burning" process of the "hardware set" of DTS.
    Then all should be fine.
    We should now know that this not always is the case. "Stuck" sensors like many have reported for E8n00 indicates one (of probably many) errata.

    The only way to monitor "real" temp is to hardwire a calibrated sensor into the case (to measure casetemp). This has long been documented in Intel white papers.
    To do IR to measure is difficult/impractical for OC/ordinary use (as shown by "unclewebb") as it means you have to run your system without any HS/cooling.

    My conclusion:
    Just give a damn in "temperatures", but go for safe stable 24/7 use.
    Or go for "broke" setting personal records as we do here on xs.org.

    "Temps" are just numbers. Sometime they may be "real" (accurate) temperatures, but most of the time they are not.
    I think.
    Last edited by TL1000S; 03-31-2008 at 03:46 PM.

    3DMarknn - 79506/96025/33499/25592

  21. #571
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    I have an E8400 installed at the moment and it is the whole reason that I decided to write RealTemp. The reported temperatures for it just didn't seem right.

    The heatsink is off but I've got a small high speed fan pointing towards the CPU.



    Some users might think that without a heatsink attached that core temperatures would be out of control but far from it.



    They were dead stable for over 15 minutes which was long enough for SpeedFan to draw a complete graph with only brief moments of the temp going up by 1C and then dropping down again.

    After 15 minutes of this it was time to get out the IR thermometer. There was no hurry so I had a chance to scan around until I found the highest temperature which was 38.8C.



    CoreTemp is using TjMax=105C and SpeedFan is using TjMax=100C.
    RealTemp is using TjMax=95C combined with its exclusive Idle Calibration feature.

    Have a good look at those 3 programs and you decide which one seems to be displaying the most honest core temperature.

    To believe TjMax=105C, you have to go completely against Intel's own in house testing of their processors at idle. Bit 30 of MSR 0xEE is not valid for this E8400.

    If you would like to check your own processor you can use CPU-Z and do a Register Dump or you can head to openlibsys.org and download OlsMsrEditor 1.1a. Both programs will let you read MSR 0xEE.

  22. #572
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    @Unclewebb:
    Excellent documentaion of your work/research.

    It would be interesting to do the same exercise provided I got me an IR-meter.

    So far I have concluded that my E8400 must be totally wrong regarding DTS/TjMax settings.
    There is no way Core0 can be 11 degrees @ 1.33VCore (idle) as reported by Realtemp assuming TjMAx=95.
    The DTS for Core1 we can conclude is "stuck"/malfunctioning (see previous posts).

    I think you will have to test quite a few E8n00, Q6n50, E4n00, E21n0 before concluding anything regarding a "pattern" between observed temp using IR-meter related to a certain TjMax offset.
    Ideally there should be a pattern as there should not be significant deviation between CPU's on a wafer/different wafers using the same production technology.
    But clearly we regulary see "batches" of "hot" vs "cold" versions of a given CPU (ie Q6600 B3 vs Q6600 G0).

    3DMarknn - 79506/96025/33499/25592

  23. #573
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    Quote Originally Posted by TL1000S View Post
    But clearly we regulary see "batches" of "hot" vs "cold" versions of a given CPU (ie Q6600 B3 vs Q6600 G0).
    Intel explains that as "the higher thermal solution performance of the Intel® Core™ processors" for explaining the higher tcase revisions of same processor.

    For example, E4x00 comes in two flavors,
    CPUID 6F6 or 6F2 with tcase 60C
    and the higher thermal version CPUID 6FD or 6FB with tcase 72C

    Q6600 G0 stepping has tcase 72C
    Q6600 B stepping has tcase 61C.

    Since Tjmax=tcase +theta(core-case)xTDP, it is likely that the B stepping Q6600 and others with tcases in 60 have tjmaxs lower than those with tcases in 72 range.

    Someone with E4x00 with tcase of 72 needs to check IR reading to compare with IR reading of Unclewebbs as he has the 60C tcase version. Same for GO versus B stepping quads. Given theta(core-tcase) is likely not that different, it would suggest a 10+ difference in tjmax, hence cause the B stepping quads to possibly read temps artificially too high. But wont know for sure til someone IR's one.

  24. #574
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    TL1000S: My personal opinion of your processor is that the DTS on one of your cores is stuck and the other is suffering from the "reporting way too low" problem that Brama had a few pages ago. If that is the case then it's impossible for RealTemp or any other program to give you accurate idle temperatures without a thorough IR thermometer calibration. I still believe that TjMax=95C across the entire E8x00 series but I'd need a big box of processors from different batches and my IR gun to definitively prove it. For some reason, I don't think Intel would be in any mood to share after seeing my Test Sensors feature.

    rge: The funny thing about my E2160 is that it has the higher Thermal Specification of 73.2C but all of my testing leads me to believe that TjMax is only 85C. My original E6400 had a TjMax=85C and a Thermal Specification = 61.4&#176;C. I lost faith in trying to figure out TjMax based on Thermal Specification after this.

    RealTemp does assume TjMax=85C for the B3 Q6600 vs 95C for the G0 Q6600. They were ready to hang me on one forum for this theory but no one has stepped up, yet, to prove me wrong. A user on XS complained about this but after he did some testing, he wasn't able to show me anything to contradict my original TjMax assumption. A B3 Quad contains two B2 dual cores which have a TjMax=85C so I've assumed that the B3 would be the same. If someone wants to loan me one I'll be happy to do a thorough test.

    TL1000S: Does a (++) Idle Calibration get your idle temps close to believable? This feature is not exact but I thought for you processor it might be pretty close on the one core that isn't stuck. Show us a RealTemp screen shot vs your water temp if you can.
    Last edited by unclewebb; 03-31-2008 at 06:56 PM.

  25. #575
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    I'll explain in other ways to the individuals of main relevance here and we will continue discussing and investigating with honesty. I think I've retreived what was needed but as the inidviduals concerned know I'm restricted quite heavily now, apologies.

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