CPU vs core temp discrepancy

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Valnar

Supreme [H]ardness
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I'm trying to troubleshoot a potential sensor issue with temperature monitoring on my new DFI board and a Q9300 I picked up from eBay. Core temps (Core Temp, RealTemp) are very high, but "CPU" temperature as listed in BIOS, Speedfan or Smart Guardian seem about right. Heatsink is the Xigmatek S1283, so everything should be fine. Heatsink is very cool to the touch at idle, and barely warm on load. Tried reseating multiple times - use AS5. It's on there good.

CPU idle / load: 34c / 54c
Coretemps idle / load: 51c / 67c (approx, since there are four cores)

I adjusted the TjMax offset down 10 degrees (from 105 to 95) and temps are still listed high. If I left it at 105, those coretemps would be 10c higher!

Is it possible I have a bad Q9300, or do I need to adjust TjMax down to 80 to make it more inline with the "CPU" temp?

Second question for everybody......
Are your CPU temps (Speedfan, BIOS, etc) inline with your Coretemps?

Perhaps it's just the offset that is messed up in all my programs? But even so, few others have such an issue. I've not heard of anyone else with a TjMax of 80c, which is what I would need.
 
The CPU temp is bullshit. As an example. It's 30 °C in my case right now as per a digital thermometer. Realtemp is reporting my core temps 32-33 °C. My "CPU" temp is reported as 26 °C which is a full 4 °C under the temp in the case which is a physical impossibility.

Use realtemp to measure your coretemps. You can believe the values you get from it. Ignore your "CPU" temp as they are often dependent on BIOS revisions (I've seen mine drop 10-12 °C after updating the BIOS on my old board).
 
My temps are still way too high, even with adjusting to 95c. They aren't really that high though. Can't be. I'm also at stock. I cannot even overclock much with this as my baseline. OCCT stops in just a couple minutes because it "thinks" I'm overheating.
 
I tried a E6600 that somebody let me borrow. Temps for all programs were like this:

CPU idle/load: 24/47
Cores idle/load: ~28/49

This is a good ol' 65nm Core2Duo E6600 and as you can see, everything looks fine running Prime95 with a nice heatsink. The only explanation I have for my Q9300 is it must be a TjMax 85c or so. I didn't know such an animal existed, but if you do the math assuming "CPU" from the BIOS/Speedfan is correct, it works out to at least 20 below the "standard" of 105c for older CPU's.

Sheesh.
 
Valnar said:
Core temps (Core Temp, RealTemp) are very high, but "CPU" temperature as listed in BIOS, Speedfan or Smart Guardian seem about right.
Click to expand...

2 totally different temperatures. E.g. for a Wolfdale CPU, the CPU temp is the Tcase temperature and is usually at the centre of the IHS determined by a analog thermal diode. This is the temp usually read by BIOS and some other monitor programs.

Coretemp and Realtemp measure the Tjunction (digital temperature sensors in the core(s) of the CPU, underneath the IHS. They will always be hotter than your Tcase (unless your PC is in a furnace and the CPU heatsink is putting heat into the cores rather than the other way around).
 
Technophobe said:
2 totally different temperatures. E.g. for a Wolfdale CPU, the CPU temp is the Tcase temperature and is usually at the centre of the IHS determined by a analog thermal diode. This is the temp usually read by BIOS and some other monitor programs.

Coretemp and Realtemp measure the Tjunction (digital temperature sensors in the core(s) of the CPU, underneath the IHS. They will always be hotter than your Tcase (unless your PC is in a furnace and the CPU heatsink is putting heat into the cores rather than the other way around).
Click to expand...

Yep, I realize this, but there must be some ballpark correlation between the two with the actual core temps of course being a little higher. Mine were like 25 degrees off with the 105c TJMax setting. Assuming the cores will be about 5 degrees hotter than the CPU diode (seems to be the google average), then my TJMax must be around 85c for this Q9300.
 
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