Which temp sensor would you trust?

[-Anomie-]

Just started OC'ing my new build (see below) last night and noticed that Real Temp 3.40 is consistently reporting my core temperatures as 15C higher than Easy Tune (the overclocking/monitoring utility that comes with Gigabyte boards). Which is more accurate? My brain says I should believe Real Temp (showing ~80C max), but I'm to the point where every degree counts and I really want to believe the Easy Tune numbers (65C max) . This is OC'ed to 4.15ghz at 1.385 volts (so far).

Has anyone had much experience with Gigabyte Easy Tune and know if the temps it reports are accurate, or way off?

System Highlights:
Core I7-930 (D0)
Corsair H50 cooler w/monster 150cfm 120mm fan
Gigabyte GA-X58A-UD3R
Crucial Ballistix 1600, 6gb
XFX 5870
Corsair HX1000 PSU

 

[BillParrish]

Unless they have radically changed Easy Tune it is reading thermistors on the board and not core temps. Thus it will consistantly read lower and slower. One easy way to make sure is to bring both apps up and while watching temps fire something heay duty up like Prime95. Coretemp will instantly go to a high temp and only change a little as the heatsink warms up. Easy Tune if reading the thermistor in the cpu socket will rise much less fast before the temp stabilizes.

Long story short, coretemp/realtemp is what you want to beleive and is what we use for comparisons. And the thing you really want to watch is the Delta to TjMax. This tells you in deg C how many deg C you have until the CPU puts out the "I am too hot" signal to spin the fans to 100% and begins throttleing. As every CPU is indivdually set at the factory for TjMax the number coretemp/realtemp uses is a good estimate but your CPU might be off as much ast 5C. The delta to TjMax is the raw data from the CPU giving that "headroom" number in Deg C and it is kinda like a countdown. When it hits zero - too hot.

Now all you have to do is decide how much thermal headroom you want to run with. Most of us (cant and not trying to speak for all) like around 15-20C of delta to TjMax under full load. Typically other things will determine your max temps depending on where you can go with your clocks and memory settings etc. In theory you can run with a Delta to TjMax of 1C and the CPU is "happy".

Tons and tons written on this, do a search for TjMax Here is the classic thread on core temps. http://hardforum.com/showthread.php?p=1031827510#post1031827510 (post # 31)

Unless they have changed it the only thing easy tune is good for is checking some voltages they do not show you in the bios. So easy tune is accurate but is not reading the same thing.

Easy tune = on board thermistors (cpu and board/system temps)
Realtemp= Digital Temp Sensor embedded into the cpu core circuity.

 

[-Anomie-]

Unless they have radically changed Easy Tune it is reading thermistors on the board and not core temps. Thus it will consistantly read lower and slower. One easy way to make sure is to bring both apps up and while watching temps fire something heay duty up like Prime95. Coretemp will instantly go to a high temp and only change a little as the heatsink warms up. Easy Tune if reading the thermistor in the cpu socket will rise much less fast before the temp stabilizes.

Thanks Bill, I've been testing with Prime95 like you said and that's exactly what's happening. I'll check out the link you posted for more info.

Currently I'm up to 4158mhz (198 x 21) at 1.33 Vcore, but my max temp is 85C so I might have hit the ceiling with this cooler. I'm on my way to the hardware store to pick up some things so I can do a little fan modding to improve airflow and then we'll see what happens.