Intel has stated 100C. Look at post number 2152 on page 87.
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well, if ''They..'' say 100 C , so ok then ... :) no problem .. i made/ run '' my own worst case scenario '' myself with my (immortal :rofl: ) E8400 @4050mhz /full air cooled Rampage Extreme
so left 2 instances of RealTemp (v.2.70 on 95C TjMax and v.2.75 on 100 C TjMax ) both are NOT 'idle' CALIBRATED, though ,
i know that CPU have bad? 9 C degree idle delay/difference between core#0 & core#1 ,
but when approaching close to the '' boiling point '' ( ~ 80 ~ 85 C ),
the delay will be gone ( 'numbers' by my understanding of course, are depending on tjmax value set by monitoring program )
also leave Everest to do the monitoring graph for throttling .. BTW everst was set
on 'Automatic' so i assume it take tjmax-100 ..
there was *CPU TM Function* ENABLED in RE bios
screen 1: it has run Prime over an hour when '' my own worst case scenario '' kicks :) /this means - i lift off CPU fan from Noctua NH-C12P , graph show CPU temp it rising up ... to throttling point ..
http://img300.imageshack.us/img300/4...1629dj2.th.png
screen 2: cool down / fan back on cooler , prime stopped my self
http://img380.imageshack.us/img380/1...3005mf0.th.png
so with my setup , this the throttling point moves upper 5C degrees from -- 94C to 99C -- according to new version of RealTemp v2.75
see the '' Maximum '' field on Realtemp panels
Yep, when you alter tjmax, you alter the temp that is displayed at DTS=0 (throttling), but of course you do not alter the actual throttling temperature, whatever that is somewhere between 95 and 100. So if you raise tjmax 5C, the displayed temp at throttling is 5C higher (though actual temp does not change). If you set tjmax to 70, your cpu would still throttle at 95-100C, but the temp displayed would be at or near 70C.
Intel says 100 Tj. Max. Do the majority agree with that number? I saw it has +/- next to it and a 97c-98c. So what is the best Tj. Max to use? Or is the jury still a long ways from deciding?
i43: Now that Intel has declared that TjMax=100C for your E8400, RealTemp 2.75 and CoreTemp 0.99.3 are finally in agreement, at TjMax at least!
The only thing left to argue about is that one of your sensors suffers from "slope error" as Intel likes to call it. CoreTemp doesn't let you do anything about that. You could try doing the RealTemp calibration or you could assume that core1 is more or less right and set a Calibration factor of approximately -5.0 for core0. Adjust that number if you have to so that your core temps are equal at idle. Use the Intel approved TjMax=100C for your next test.
Try running different loads and see how your two cores track each other as the temps go up and down. Does the latest calibration formula in v2.75 allow your two cores to report similar temperatures when the load is the same on both cores? Just curious. I know how much you like to test so I thought I'd give you something new to check out. :)
I just want to show users that even with the same TjMax, something still needs to be done with the "slope error" many of these 45nm processors have.
Freaky Freezer: Intel has stated TjMax=100C so we have to go along with that. They've also mentioned that these sensors can show significant slope error at lower temperatures and that TjMax is not an exact number. Plus or minus a couple of degrees at TjMax might be pretty typical but Intel didn't release an official range and likely never will.
unclewebb, I'm using a Tj. Max of 95c. Just to get a final word from you, you agree that Tj. Max of 100c for the E8400 is the best to use?
Also, at a current Tj. Max of 95c. My E8400 sits idle between 30-34 and 30-35, is this the "slope error" you're referring to? Or have I improperly applied thermal paste?
Freaky Freezer: For an E8400, I would suggest using the Intel recommended value of TjMax=100C. Intel hasn't released enough information about how that number is determined or what the typical range of error in that number is. For 45nm, there is likely a couple of degrees of error in that number but no easy way to determine or prove an exact TjMax value so all we can do is accept what they've told us.
If you take the time to try and calibrate RealTemp to your sensors as outlined in the documentation, any slight error in TjMax will be reduced.
http://img187.imageshack.us/img187/9272/dtstemppu4.png
"Slope error" is when two sensors at full load provide very similar temperatures but at idle they can differ significantly. If you graphed this on a piece of paper, the two temperature curves would be at different slopes.
In my example, at 70C both cores are reporting the same temperature. In a perfect world, if these sensors moved at the exact same rate as the temperature changed, they would both decrease at the exact same rate and follow that pink line in the middle. At idle they would both report the same, correct value of 35C.
In this example let's assume core0 is the yellow, top line. The sensor data changes at a slower rate than the actual temperature is changing. By the time both cores have cooled down to 35C, it is still reporting 45C which is wrong. Core1 does the opposite. It's sensor is overly eager and it changes in value faster than the core temperature is changing. When both cores have cooled down to 35C, core1 has gone crazy and is only reporting 25C. That makes for a huge difference in reported temperatures between two cores that are actually the same temperature.
My example that has two cores reporting a 20C difference might seem a little extreme but if you go back a page or two in this thread you will see that JohnZS has an Expensive processor with a difference at idle of 15C between cores. Intel has been nice enough to tell us that this problem exists but hasn't given us any approved way to compensate for this problem. RealTemp uses a formula to compensate for this and lets a user try and figure out if his cores are reading too high or too low.
Read the documentation and send me a PM if you need some more detailed help with the calibration procedure.
unclewebb,
If calibrated with 95c and it was right on would you still go with 100c?
http://www.xtremesystems.org/forums/...postcount=1740
I am using 100c now but I think 97c would be more accurate (or as accurate as can be expected)?
Thanks
Thank you so much unclewebb. I really appreciate your in depth response. I won't do any calibrating because in all honesty I use Everest for all my temps and the new version of Everest only allows increments of 5 when adjusting Tj. Max. So if I find out my Tj. Max is 97-98, I wouldn't be able to enter that data into Everest anyway. I did use an earlier version of RealTemp and it worked great but I just have all my other temps under Everest so it's easier to just use that. But thanks again.
F%$#ing Intel
kpo6969: Officially, Intel says TjMax=100C so for compatibility I'm going to be recommending that. For maximum accuracy, TjMax=97C looks like a good pick for you. If you go with TjMax=100C then for better accuracy you'd probably need to use a small negative calibration factor to get better idle temps. Intel says that TjMax is not an exact number so if you need to move it around a couple of degrees then I no longer see that as being a problem.
I have my Q6600 in at the moment and it doesn't seem to have the slope error that many 65nm sensors do. When using TjMax=100C and assuming a 5C gradient between IHS and core, it seems to track pretty well.
I've gone up to about 80C so far with it and the small differences between cores is staying fairly consistent. I'm only at idle and the heatsink is just floating on top but it seems to indicate a slight difference of TjMax from core to core. I used to avoid manipulating TjMax because I assumed that it was a fixed value but adjusting it by a degree or two might be the best way to get the temps equalized on this processor. Now that Intel has said that there can be a slight variation in TjMax from one core to another, a slight manipulation in TjMax looks like a new option.
If two cores stay a small fixed amount apart from idle to your maximum temperature, I'd try to use a TjMax adjustment and if the difference between cores decreases as things heat up then I'd go with the standard RealTemp calibration adjustments to correct for "slope error."
I just finished reseating my GTX waterblock on top of my E8400. First I cleaned it, purified it and applied AS5 according to arctic silver's directions for a dual core CPU. My temps are still 4-5 degrees apart between Core's 0 and 1. Anyone have any ideas?
(35C and 39C at idle with Tj. Max of 100. It is overclocked to 3.9ghz at 1.344 Vcore with EIST and and C1E enabled. Room temp is 23.5C and case temp is 40C. Are these temps good, bad or average?)
My smart Guardian reads my CPU temp at 23C-25C. What sensor is Smart Guardian reading? Tcase temp?
i just want to ask what's the correct tjmax to set in realtemp 2.75 using Q6600 processor?
keep up the good work uncleweb! :up:
thanks in advance! :)
DJSUB: Based on E8400 testing and Intel using TjMax=100C for that processor, a Q6600 - G0 measures exactly the same so we'll have to assume TjMax = 100C for that one as well. Using TjMax=100C results in the core temperature being reported about 5C higher than what an IR thermometer measurement of the IHS shows. That is the difference that Intel wants us to accept though it might be a degree or two on the high side for the average processor. The Q6600 - B3 stepping as well as all of the original B2 series and the L2 series will be adjusted to TjMax=90C in the next release of RealTemp.
Freaky Freezer: I tried to hint that your problem is not likely a thermal paste application issue. Read the RealTemp documentation and try doing the calibration procedure and you'll have a better idea of how much each sensor is off at idle. You can have one sensor high and one low or both of them high or both of them low at idle by different amounts. The only way to figure this out is to do some testing. The bad news is that Everest and CoreTemp don't give you any way to correct for this problem. Since you like Everest, you have to get used to your idle temps being reported differently.
I kind of figured as much, which is why I didn't bother with the calibration uncle. Maybe Everest in a new version will allow for a more specific adjustment of Tj. Max and then I can do the calibration.Quote:
The bad news is that Everest and CoreTemp don't give you any way to correct for this problem. Since you like Everest, you have to get used to your idle temps being reported differently.
Although since the re-application of thermal paste and setting Tj. Max to 100C, I'm reporting temps between 35c-37C and 35C-38C. A little better than the 4-5 difference before hand.
Here's some testing I did using the Intel approved TjMax=100C for my E8400. I also did this same test with a Q6600 - G0 with TjMax set to 100C and got the same results.
I played around with it for half an hour and even took it a little beyond TjMax just to make sure that it was thoroughly warmed up. :)
http://img528.imageshack.us/img528/4043/rt4601wz7.jpg
I tried testing at different temperatures and moved the IR gun around and around but the hottest it would ever show was 5C less than the reported temperature of the hottest core. This is the gradient that Intel says exists between IHS and the core even when the CPU is 99% idle. The above pic was taken 2 seconds after this one.
http://img409.imageshack.us/img409/6674/rt4602he4.png
Once I put it back together I tried doing the RealTemp calibration test. The room temperature near the open computer was 21C and it was running at 1600 MHz and 1.08 volts. With these settings, at idle, an expected core temperature should be about 5C above the room temperature which would be 26C. This is what I get:
http://img409.imageshack.us/img409/5...400idlepq4.png
When using the correct TjMax, and no additional calibration, my core temperatures are being reported about 8C too high. This is a perfect example of "slope error." JohnZS has one core that reads too high and one core that reads too low so a combined error, when uncorrected, of 15C on his Quad is hardly surprising.
Intel finally releasing the correct TjMax for 45nm hasn't given the enthusiast community as much information as they thought they were going to get at IDF.
Here's a quote from the press release that was posted at Anandtech:
"Armed with this information, seasoned application developers and amateur coders alike will finally have everything they need to implement the most accurate, real-time core temperature display tool possible."
Well, not quite. :rofl:
forgive me uncle but you lost me. You said core temperature is usually 5C higher than room temp, which is 26C. So core temp should be 31C right? And you're showing 34C. So why is it 8C too high?
Also, my Smart Guardian is showing an Idle temp of 21-22 for the CPU, is it reading off the Tcase sensor? And if so, does that give any inkling as to what my core temps actually are?
Room temperature is only 21C so 21 + 5 = 26C which is 8C less then the 34C that is being reported.
I finally had a chance to compare my TCase reported temperature to the IR gun and it was 7C higher than what RealTemp was reporting with TjMax=100C. I've never trusted TCase readings from my board. Some boards are better than others but there's no way to tell by looking at it how well calibrated the TCase readings are.
Unc,
Click on the link in my signature to use Section 9 (Calibrations), Part 1, in my Temp Guide to tweak an offset into SpeedFan, to correct for Tcase inaccuracy from BIOS.
EDIT: If you're running your Q6600 G0 (idle 16 Watts) and your Tuniq Tower (high-end cooler), then Tcase idle should be ambient + 3c. Check out Sections 6 and 14 to verify.
Also, note whether Tcase idle matches heat pipe IR measurements, where the pipes intersect the heat sinc. If you can find a clear line of sight, I think they'll be reasonably close. Since our Fluke's are +/- 1c, I'm interested to see if your Tcase idle observations agree with my findings.
Comp:cool:
To me the whole thing was just a clever PR exercise for the upcoming Core i7 and all of us (you, me, Anandtech, all of us here on XtremeSystems etc) got sucked into this hoping to see details on the entire Core2 range's TjMAX (by stepping) and perhaps some hints and tips and how to accommodate for error.
At the end of the day all that Intel said in blunt layman terns was,,
"Yes we know our sensors in our 45nm Core2's are a little bit rubbish, here are a few TjMAX values for a couple of 45nm CPU's....if you are thinking of measuring thermal values there is a quantifiable amount of error in doing this and this error gets greater at idle temperatures.... BUT our up and coming brand spanking new shiny Core i7 processors come with working sensors, far more accurate and reliable than our current "Extreme" Sensors
Unclewebb do you plan on making 2.75 final anytime soon?
So far I am really impressed with it as my sensors all agree throughout the range (from idle to being at 100% load during stress testing).
Have you tried contacting intel asking if they have any further information to offer to assist you in developing RealTemp?
It would be nice if they gave you or at least made a public resource of all Core2 processors TjMAX values (by stepping to).
Keep up the good work, Kind Regards
John
I sort of gave up long ago on Intel being helpful to this project. I must have been dumb to think that they would say anything good about RealTemp which shows users that their temperature sensors sometimes "bottom out", aka. "get stuck". I wonder how many RMA's that has resulted in. Once Core i7 is out maybe one of their lawyers will contact me and let me know! ;)
JohnZS: Intel's graph about the "slope error" was a little hard to interpret so I needed to do some more testing. I wasn't sure about whether core2 on my Q6600 and many other Quads suffered from TjMax error or slope error. Maybe a little of both.
I had to get that core over 90C before it started reporting the exact same as core3. That would indicate slope error and that error seems to cover the entire temperature range. If it was a difference in TjMax then that error would continue from idle up to and including TjMax.
The calibration method introduced in 2.75 is based on what my testing showed so I don't need to make any changes to that. I plan to bump up the original B2 and similar processors to TjMax=90C in the next release which should be out in a couple of days. I'll be calling it version 3.00 so users will know that there have been some major changes to TjMax and calibration and might even read the first line or two of the new documentation, maybe.
is the latest version 2.75?