AMD 64 CPU Diode temperature?

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I found a utility called nxSensor which allegedly reads the CPU diode in AMD 64 CPUs and it reports the following while stress testing:



It's a Sempron 2800+ running at 2.6Ghz with 1.55v (bios setting) on my new DFI UT NF3 250Gb. The motherboard based CPU temperature is reported as 46c whereas the CPU diode temperature is a staggering 80c!!! I can even make it go beyond 90c for the diode temperature by running S&M at the same time as the two Prime95s.

The Sempron 2800+ can run up to a maximum temperature of 69c as can be seen here and according to the motherboard I'm nowhere near that although according to the diode temperature I'm way beyond it! :eek:

Anyone know anything about the diode temperature reading and is it possible nxSensor is reading it wrong? :confused:
 
Bah the above stress testing caused the system to freeze requiring a reboot so I guess the CPU diode temperature reported by nxSensor might actually be correct so it's now back at 2.4Ghz with default 1.4v and the motherboard CPU temperature is 39c and the CPU diode temperature is 60c:



:(
 
I get two vcores reported too so I just unticked the second one and the others that seemed wrong.

What motherboard CPU temperature did it report and how does it compare to the diode temperature?
 
The nxSensor page says it gets the CPU diode temperature from the internal diode in the CPU and yours at 47c and 58c looks good especially when compared to my results!

I'm currently using the stock cooler but I'll try a better cooler soon and see if it helps.

Anyone else care to try nxSensor and post their results? :)

Get it here: http://cbid.amdclub.ru/html/download.html

Direct download here: http://cbid.amdclub.ru/files/nxsensor.zip
 
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It's on the main CBID page down the bottom right and says:

The final version of NextSensor 2.3 has been released! It incorporates a new unique feature that provides sensing the temperature of any AMD64 processor using its on-die thermal diode! Besides, there is an ability to monitor voltage, temperature and fan speed parameters via NextSensor Remote Monitor function in conjunction with any web browser! Now administrators can effectively control their systems in LAN or via Internet. Enjoy!
Click to expand...
 
Jimbo Mahoney said:
No.
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Jimbo, surely it must be different?

The motherboard CPU temperature (PROCESSOR in nxSensor) reported is the same as other programs report but it's lower than the reported internal thermal diode which makes sense to me suggesting it really is reading the internal thermal diode and most systems probably don't do that hence the different readings.
 
Mr Mister said:
it says my cpu fan is running at 8700rpm.... i dont think so. :p
Click to expand...
You will probably need to select the correct sensor in the Control tab. I had to switch to the ITE IT87xxF sensor for it to report everything correctly for my DFI UT NF3 250Gb.
 
I'm off out and gonna leave it running dual Prime95s and will be able to check the temps on my mate's PC. :D

EDIT: Check my 12v line it's awful. I need my Antec 550w back from RMA asap! :)
 
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It's the IP address your ISP gives you. So for me it's 84.9.233.238 and the port default is 8088.

I also had to login to my router and setup a firewall rule so it could be accessed from the outside world.
 
Wow 1.7v and those temps! :cool:

That is spectacular cooling you have there Jimbo. I'm gonna have to get into water cooling too. :)
 
Yeah the conflicting information is annoying although we can see 52c and 57c in nxSensor which is also being reported in MBM except they're labelled differently. The 59c in nxSensor prolly would be also visible in MBM by configuring sensor 3 with one of the unused sensor lines.

I wonder if the on-die thermal diode reports differently for dual core CPUs which again makes it even more confusing.

I wish I could find public domain info on the sensor programming as I could easily write my own temp reading program if I had something to go on (I can do kernel programming, etc) and also get help on here to research the results. I've tried searching google though but haven't found much at all. :(
 
I removed the stock cooler and it's real obvious it wasn't making very good contact with the CPU. The thermal compound wasn't spread very thinly on the CPU and heatsink suggesting there wasn't enough pressure on the CPU. I've no idea why the motherboard CPU temperature wasn't reporting the bad contact but for sure the on-die thermal diode was!

I've installed a new Freezer 64 Pro which is making very good contact and at 1.525v at 2.6Ghz the motherboard CPU temp is 38c and the thermal diode temp is 62c while running Prime95. :cool:

Also my DFI UT NF3 250Gb's CPU temp reporting looks to be useless as it's idling at 29c and the load of 39c vs the thermal diode temp of 62c is way too much of a difference for my liking. :rolleyes:
 
Juno, CPU-Z should report the sensor used on your motherboard and hopefully it's accurate. You can find it in the CPU-Z Mainboard tab and whatever it says is hopefully available as a selection in NextSensor which should get you the correct voltages/fans speeds/temps.
 
Yeah I guess it's each program matches the sensor temperatures to whatever labels the programmer decided to use hence why different programs label the sensor readings differently.

I guess it's motherboard/sensor chip specific so only way to match them up is to have a database of motherboard/sensor chips/correct labels or allow the user to match them up manually. :(

Also running lots of sensor reading programs at once can result in different temperatures depending on the update frequency and the accuracy when for example two programs read the sensors at the same time. The temps can fluctuate too hence why a few degrees difference can appear in one program compared to another.
 
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SmartGuardian? I would say so as I've checked it on mine and it reports the same as my properly configured/labelled Next Sensor results. It also helps to understand VCOREB in Next Sensor, it's the chipset voltage and it matches the chipset voltage in SmartGuardian.
 
Here's mine running two Prime95s and shows SmartGuardian and Next Sensor:



Hopefully I won't get any freezing/crashing/Prime95 failing as the temps are looking good so far.
 
The main thing with Next Sensor is you can enable the reading of the on-die thermal diode which should give you an idea of the real maximum temperature your CPU is reaching and I would guess with your current setup it'll be around 65c to 70c?
 
Well from my limited experience of it the on-die thermal diode gives a good indication if too high a CPU temp is what's causing Prime95 to fail or the system to freeze or crash while stress testing.

You mentioned previously your current setup failed Prime95 after a few hours and if you check Next Sensor you might find the on-die thermal diode is actually reporting a temp that highlights why it's failing ie the actual temp of the CPU is too hot but you can't really know that by relying on the motherboard reported CPU temp as 49c isn't really too hot.

So yeah check the on-die thermal diode via Next Sensor please mate. :D
 
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OK! :D

I'm gonna leave mine running overnight. This DFI is way better than my MSI Neo Platinum so hopefully I'll wake up to a still running PC. :)
 
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