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How do you measure your CPUs temp?

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  • CPUs
Last response: in CPUs

How do you measure your CPUs temp?

Total: 30 votes (8 blank votes)

  • SpeedFan
  • 23 %
  • Real Temp
  • 28 %
  • Core Temp
  • 32 %
  • CPUID Hardware Monitor
  • 10 %
  • Other
  • 10 %
July 26, 2008 12:45:48 AM

A recent problem give me things to think about. Temperatures are extremely important for a stable computer, more if one plans to overclock. Several programs out there measure the temperature of our CPUs, yet... almost everyone gives different results... Which to believe? If they measure the same, how can the results be so different? Im talking about 10c variations between some of them...

Oh well... What do you use and why?

More about : measure cpus temp

a b à CPUs
July 26, 2008 1:35:19 AM

I use real temp because I'm too lazy to calibrate speedfan.

July 26, 2008 2:47:30 AM

CoreTemp is high & RealTemp is low. Speedfan is in the middle, & probably safer.

CoreTemp & RealTemp, although about a 10c difference, both report the same distance/delta to TjMax. Whatever the TJunction is set to, the distance/delta to TjMax stays the same.

So keeping the distance/delta to TjMax above 30c-35c would probably be a safer way to measure temperature.
Related resources
July 26, 2008 3:07:55 AM

realtemp, when calibrated, it is dead on.
July 26, 2008 3:26:52 AM

shadowthor said:
realtemp, when calibrated, it is dead on.

By dead on, do you mean changing the TjMax or leaving it as is?
The CPU temperature maybe, but what about core temperature?
Since no one knows the TjMax, how can you be sure? On 45nm RealTemp uses 95c TjMax , SpeedFan uses 100c TjMAx, & CoreTemp uses 105c TjMax.

I guess since you can change TjMax in RealTemp & if you knew what the TjMax was, then you could calibrate RealTemp to be dead on?



July 26, 2008 3:30:06 AM

pc probe ftw
July 26, 2008 4:04:50 AM

I use the old "hand over the coals" Boy Scout hot fire test.
July 26, 2008 4:43:23 AM

level101 said:
By dead on, do you mean changing the TjMax or leaving it as is?
The CPU temperature maybe, but what about core temperature?
Since no one knows the TjMax, how can you be sure? On 45nm RealTemp uses 95c TjMax , SpeedFan uses 100c TjMAx, & CoreTemp uses 105c TjMax.

I guess since you can change TjMax in RealTemp & if you knew what the TjMax was, then you could calibrate RealTemp to be dead on?
Real Temp measures the core temp, not case temp.

Real Temp is the best by default because unclewebb, the author, has taken great pains to do actual testing of the tjmax for some of the processors. Don't believe me, read it for yourself.

XtremeSystems Forums - Real Temp


a b à CPUs
July 26, 2008 1:28:18 PM

Ok while we're on the subject... can somone tell me if I should be setting a tjunction max of 95c or 100c for my q6600 b3?

a c 118 à CPUs
July 26, 2008 2:30:49 PM

It all depends on the machine I am using as all of mine are different and either require or work better with a different method of monitoring.

1. Desktop (X2 4200+)
- Sensor used: CPU core digital temp sensor (driver = k8temp)
- Monitor used: GkrellM

2. Notebook (C2D U7500)
- Sensor used: CPU core digital temp sensor (driver = coretemp)
- Monitor used: GNOME hardware sensor applet (screen is too small for GkrellM to sit off on one side)

3. HTPC (900 MHz Celeron Coppermine-128)
- Sensor used: ACPI thermal zone temperature reading from on-package Analog Devices sensor
- Monitor used: The machine is only hooked up to a CRT TV, a homebrew RS-232 IR remote receiver, and a wireless bridge, so I just execute a "cat /proc/acpi/thermal_zone/THRM/temperature" when I want to see the temperature. This sensor is known to be needing a certain offset that is outlined in the "Intel Celeron up to 1.10 GHz" data sheet, so I have to mentally add about 5 C to the temperature to get the proper temp, +/- 1 C.
a c 1207 à CPUs
July 26, 2008 3:16:38 PM

I have used Asus Probe and MSI Core center since they have come bundled with the MB I am or have been using.
July 26, 2008 5:44:49 PM

sportsfanboy said:
Ok while we're on the subject... can somone tell me if I should be setting a tjunction max of 95c or 100c for my q6600 b3?
Here is your answer, from the author of Real Temp.
Q6600 Tjmax
a b à CPUs
July 26, 2008 6:46:42 PM

Fantastic!! Thx Zorg

Edit: erased my first edit
July 26, 2008 7:06:08 PM

Another alternative to feel safer, is to go by the Tcase sensor. That would be the sensor that your bios reads, MB utility App, SpeedFan also reads it. It tricky with Speed Fan since you will need to figure that out on loading your cores to watch the temps go up. Sometimes it labeled CPU, other temps it maybe Temp1 or Temp2, which can be re-named.

I only say this since Intel does publish the thermal spec of a CPU, and generally would be the Tcase max, in which you shouldn't exceed.

However I think its still niffy to be able to see the separate core temps.

On a side note, you can adjust the tjmax on Coretemp/RealTemp, and offset cores on SpeedFan. For Vista (since speedfan doesn't reconize my gpu temp) I use speed fan to show the Tcase temp, while coretemp shows, obviously the core temps. (edit: display on the taskbar)

So I don't exactly have a favorite. :lol: 
a b à CPUs
July 26, 2008 7:16:54 PM

Just realized that the processor in the picture is a GO stepping q6600. I think that's why I was confused when I originally read the info on realtemp.

Is my tjunction max still the same as the go stepping revision, even with a lower tcase max? B3=62 GO=70 (I believe it's 70)
July 26, 2008 8:33:07 PM

sportsfanboy said:
Fantastic!! Thx Zorg

Edit: erased my first edit
I just saw you had a B3. I don't know what the Tjmax is for the B3 and I can't find a credible number anywhere. You can calculate the Tjmax with CompuTronix's Core 2 Quad and Duo Temperature Guide. I'll PM him and see if he can shed some light.
a b à CPUs
July 26, 2008 8:51:18 PM

Cool thx again
July 26, 2008 10:01:01 PM

I got a response from Comp, he should be posting here. If not here is his response to me.

CompuTronix said:
The B3 is a pair of B2's, so Tjunction Max is 85c.

a b à CPUs
July 26, 2008 10:43:40 PM

wow, that would drop my temps by 10c, that's quite a bit. I recently have been using real temp set to tjunction max 95c.

So the noob question of the day is... Set tjunction max to 85c in real temp, and I'm good to go?
a c 308 à CPUs
July 26, 2008 11:02:32 PM

Guys,

As an enigneer, the use of proper terminology is paramount, which defines how text and specifications are written in technical manuals, and keeps discusions from being misunderstood. Terminology is simply a fundamental part of language which transcends all topics. Reading through this thread, the nature of your questions and comments are obvious, but some of the terminology is incorrect and misleading.

The title of this thread "How do you measure your CPUs temp?" is inappropriate, and confusing. CPU temperature (Tcase) can be measured by SpeedFan and Hardware Monitor, which are the only correct answers in the poll, since Core Temp and Real Temp only measure Core temperatures (Tjunction).

If you read the Real Temp documentation - http://www.techpowerup.com/realtemp/docs.php - then you know that Real Temp offers 2 calibration points; Tjunction Max and Tjunction Idle. The author of Real Temp, unclewebb, has performed extensive research, testing and analysis on key Core 2 processor variants in order to create accurate Tjunction Max tables, so even though a Tjunction Max calibration feature is provided, the default value shown is already correct. The authors of Core Temp and Everest haven't performed any testing. They simply adopt Intel's documented Tjunction Max tables for mobile variants, which differ in thermal behavior from desktops, and in some instances, aren't even close.

Real Temp is the only utility that provides a separate Idle calibration to compensate for known problems with sensor linearity, since Intel's Digital Thermal Sensors were never intended for temperature monitoring from Idle to Load. The DTS sensors are only designed to provide accurate thermal protection for Throttle (overtemp) and Shutdown. This shortcoming is more obvious on 45 nanometer processors, which are often reported with DTS sensors which "stick", and won't report actual Idle temperatures below a certain value. Only the Tcase sensor (CPU temperature) is linear from Idle to Load, and can be accurately calibrated, as well as Tjunction (Core Temperatures), using my Core 2 Quad and Duo Temperature Guide. A detailed explanation of the differences between these sensors is in the Guide.

If you use Real Temp's default Tjunction Max value and perform the Idle calibrations, then Real Temp will be "dead on". To further validate the accuracy of Real Temp, consider the following; since the techniques I developed in my Temp Guide for calibrating SpeedFan don't use Tjunction Max values to achieve accuracy, then why, after SpeedFan calibrations have been completed, does the Core temperatures agree with Real Temp within a degree or two? Check it out for yourself. Try my SpeedFan calibrations then compare your Core temperature results with Real Temp.

And yes, the B3 is a pair of B2 Cores, so Tjunction Max is correct at 85c, which is Real Temp's default Tjunction Max value for the Q6600 B3.


I hope this explanation helps to clarify and answer your questions.

Comp :sol: 
a b à CPUs
July 26, 2008 11:10:40 PM

It does thx
July 27, 2008 3:32:19 AM

Thanks for the clarification, nice post as always.

I wasn't sure if unclewebb had discriminated between the B3 and G0, as I only have a G0. It does make sense that he would have.