Faulty DTS on 3770K??

Araxie

Supreme [H]ardness
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Feb 11, 2013
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6,456
Hi all people.. im having some kind of "Issues" or in fact weird peak idle temps with my 3770K chip, my room temp Right now its 28C, (measured with 2 thermometers in 2 different parts in my room, one near my case the other in a wall 5 meters away, very accurate both). well the problem, im having very low idle temperatures and even lower peak idle temps, 28C ATM with a minimum of 23C across all cores which its kinda impossible IMO, there's no way to idle lower than ambient temp and even i've checked corsair link software and corsair report the water temp are 29C-30C and CPU temp of 30C that seems right, so I guessed a problem with CoreTemp+CPUz Pic, but then i've tested with Aida64+Pic similar temps (less idle time), then tested with RealTemp TI and again Same behavior.. so I guessed in faulty DTS or a mobo problem?. i just can believe in a lower temp than my h100i water temp, load temperatures seems to be fine, 62-65C (bear in mind my 28C room temp and tropical climate) across the cores under Aida64 FPU with 1.08v @4.2GHZ. idle volts are 0.77V i've used negative offset so idle vcore also affected (BTW couldn't be this also affecting DTS readings due to low voltage at idle?) I have all C States Enabled in Bios including Package C State support.

I really don't know what to think thats why I ask for some more ideas.. I have couple of weeks with this chip so no noticed this "Issue" but in my first 3770k a year ago this didn't happened and i was using a i7 2600 for some time and didn't happened either so i guess the rest of the system its fine.. any input will be appreciated..

regards.
 

Delitus

n00b
Joined
Jan 6, 2012
Messages
36
For Intel CPUs at least, idle temperature readings should only be used as a rough indication. The readings are known to be fairly inaccurate among different CPUs when the distance between Tj Max and Tj is larger. This is a non-issue, because as far as the CPU is concerned, temperature readings are only relevant for the purposes of triggering thermal throttling/shutdown at unsafely high temperatures, and are calibrated to do this job. Expanding on that point, the readings do become much more accurate for load temperatures (that is, when temperatures approach closer to Tj Max) - this is what you are observing now. The bottom line is, so long as your load temps look okay, you can rest assured that idle temps are fine also. :D
 

Araxie

Supreme [H]ardness
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Feb 11, 2013
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yea i know.. but its still kinda weird those kind of lower temperature readings.. it cause me heavy concerns about the load temperatures i really doubt if could be lower or higher than recorded. high 30s to lower 40s in normal day task(browsing, music etc) and mid 50s while gaming.. both seems right but im still kinda worried, because im obsessed with the temperature control in my machine.
 

unclewebb

[H]ard|Gawd
Joined
Jun 21, 2006
Messages
1,807
It's not weird at all. These sensors are chosen and calibrated by Intel to control thermal throttling and thermal shut down and nothing else. Intel could care a less how accurate these things are when your CPU is idle or lightly loaded. As long as they are accurate enough to get your CPU to start thermal throttling at approximately 105C then these sensors are good enough.

Most of these sensors read a little low when the CPU is idle. At the calibration point near 100C, these sensors are rated to be accurate to +/- 5C. They are far less accurate than that when the CPU is idle. No need to be OCD about your idle core temperatures. Everything is fine.

If your CPU ever gets this hot, then it is time to worry. :)

http://img27.imageshack.us/img27/6216/torturetest.png

BTW - if you have enabled the deep C states like C6, your offset voltages are being ignored 99% of the time when idle. The actual core voltage is dropping down internally far lower in C6 to virtually zero. Offset voltages are redundant if you are using the C States.
 

Araxie

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Feb 11, 2013
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well about C states thats new for me, good information thanks, i always try to keep enabled all C States and keep a low consumption and temperatures while idle or low tasking.. since my first 2600k i thought DTS should be pretty accurate i've started to trust it even when [H] Stopped to use thermal probe directly on the CPU Heatsink to trust in reading directly from software like Coretemp and Realtemp and most recently Aida64...

about the C states again thats good news due i know i still can add a bit more of negative offset to lower voltage.. this new 3770k its great compared to my first one in voltage requirements and temperatures.. 1.05V manual voltage for 4.2GHZ and my first one required 1.19 for same speed.. =D i will start to play again with offset.. thanks..
 
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