Overclocked CPU was running cool, now it isn't

i_hate_flying

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Dec 13, 2006
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Hi, I built this rig back in January 2007 with your help. E6600, EVGA 680i, 2 GB Corsair DDR2 PC6400 5-5-5-12 and Thermaltake Big Typhoon. I was able to overclock to 3.4 Ghz without a problem and was Orthos and Prime95 stable for 24 hours. I don't remember at what voltages, unfortunately. I've since moved twice and can't find my notes. After I updated the bios to p27, I found I couldn't get the temps I was getting before so I left the CPU @ 3.2 Ghz @ the default voltages. This was solid and the temps were like 30-35 C idle and 45 C load. Since then, the temps crept up on me. Not sure if it was the particularly hot summer we had last year, but I ended up putting the overclock down to 3.0 Ghz @ default Vs with the same kind of good temps.

Since this time, I've noticed my computer's gotten slower. Doesn't seem to run the same. I recently upped the OC to 3.4 Ghz again with a voltage of 1.3125. Everything is stable, but the temps I'm getting aren't great. 48 C idle and 58 C under regular load, 68-70 under Orthos. That's unacceptable in my opinion. I haven't hit the voltage sweet spot yet, but I can tell you that I was unable to post at 1.23125. Idle temps in the bios were about the same at that voltage, however.

I'm wondering what I can do to get my temps down at 3.4 Ghz, if anything? I'm not sure if going to the P32 bios would help, or maybe reseating the CPU with some new paste. I really, really hate taking the cooler off. My case has good cooling, but that cooler sits in such a way that I have to really work at it to get it out. Another thing I might be forgetting, the ambient temperature effect, but I don't have an indoor thermometer.

Suggestions??
 
Hmmm...honestly, an OC on that chip of 400mhz shouldn't cause that much of a heat increase. I agree with nvalhalla; are you sure you are getting enough cool airflow in your case? Canned air is your friend. You said you moved, I am guessing locally...not to say...the Sahara? If you have moved, are you sure you didn't jar the CPU cooler loose? Since you aren't going into thermal shutdown, I would assume not.

I would try CoreTemp or something similar. I've never used Orthos...not familiar with it. Temps going up are temps going up...regardless of how they are measured.
 
Dust is a possible problem, it's quite dusty in the last three places I've lived. I lived in a very polluted city in Poland where people burn coal for heating. I forgot how many metric tonnes of coal dust fall on that place every year, but you can see the black soot everywhere. It was inside my laptop, stereo, books, etc. Then I moved to Norway where the air is very clean. I have no idea where that dust came from. Since then, I moved to a small city where there's nothing in the air and where you can drink the water from the rivers. There's more dust here than there was in Oslo. But enough about that :)

I'm going to move again in a month and buy a special vacuum that catches everything in water, not a bag, so the dust situation might finally change :) However, the rig itself stays pretty clear of dust. I clean the front air intake when it starts collecting anything, and the rear exhaust is always clear. Inside, there's some dust, but it didn't seem to make a difference on the temps after I gave it a thorough cleaning last summer. I'm idling at 46-48 C now, and when I'm running normal programs, the temps are at 55. The really high temps come when I run a very intensive CPU stressing program.

I have a small mid-tower case right now, but I think it does well for cooling. I'm going to get something a little bit bigger at the end of the summer/start of the autumn. I've been avoiding it because I move so damn much!

I won't "buy a new CPU" just like that, not until it dies for good. I really don't think that the CPU is dying since this has been happening all along. It's a good CPU, I'm sure human error or something environmental is at work here.

So you don't recommend that I do anything with the bios? Latest isn't greatest?
 
I know this is prolly irrelevant, But would you mind running the latest Core Temp, and telling me what the VID of that processor is?

Thanks alot!

--Lupi
 
i_hate_flying, to which temperatures are you referring; CPU (Tcase) or Core (Tjunction)? From the Core 2 Quad and Duo Temperature Guide - http://www.tomshardware.com/forum/221745-29-core-quad-temperature-guide


Section 1: Introduction

Intel provides separate thermal specifications for 2 different sensor types; a CPU Case (not computer case) Thermal Diode located within the CPU die between the Cores, and Digital Thermal Sensors located within each Core. The Case Thermal Diode measures Tcase (Temperature Case), which is CPU temp, and the Digital Thermal Sensors measure Tjunction (Temperature Junction), which is Core temp. Since these sensors measure 2 distinct thermal levels, there is a constant temperature gradient between them, which is Tcase to Junction Delta. C2Q`s have 1 Tcase and 4 Junction sensors, while C2D`s have 1 Tcase and 2 Junction sensors.


Section 4: Thermal Flow

Heat originates within the Cores, where Tjunction sensors are located within the hot spots of each Core. Heat dissipates from the bottom of the Cores through the CPU Case, which creates a thermal gradient toward the center of the Die, where the Tcase sensor is located. Heat then dissipates through the socket and motherboard to air inside the computer case. Heat also dissipates from the top of the Cores through the Integrated Heat Spreader and CPU cooler to air inside the computer case. Safe and sustainable temperatures are determined by CPU cooling efficiency, computer case cooling efficiency, Ambient temperature, Vcore, clock speed and Load.

Tjunction is always higher than Tcase.

Tcase is always higher than Ambient.


Section 5: Findings

(A) Tcase is acquired on the CPU Die from the CPU Case Thermal Diode as an analog level, which is converted to a digital value by the super I/O chip on the motherboard. The digital value is BIOS Calibrated and displayed by temperature software. BIOS Calibration affects the accuracy of Tcase, or CPU temperature.

(B) Tjunction is acquired within the Cores from Thermal Diodes as analog levels, which are converted to digital values by the Digital Thermal Sensors (DTS) within each Core. The digital values are Factory Calibrated and displayed by temperature software. Factory Calibration affects the accuracy of Tjunction, or Core temperatures.

(C) Tcase and Tjunction are both acquired from Thermal Diodes. Tcase and Tjunction analog to digital (A to D) conversions are executed by separate devices in different locations. BIOS Calibrations from motherboard manufacturers, Factory Calibrations from Intel, and popular temperature utilities are frequently inaccurate.


Section 15: Troubleshooting

(D) BIOS updates will affect the accuracy of Tcase, but will have no affect on Tjunction.


As you can see, it's important to be specific when discussing temperatures.

It appears that from what you've described, your temperature increase stems from your BIOS update, which is a common problem. I've seen several consecutive BIOS updates on certain motherboards which had inaccurate CPU temperatures that varied from 10c below ambient to 25c above ambient at Idle. I've also seen different Quad Core processors which had inaccurate DTS calibrations resulting in Cores that varied from 8c below ambient to 39c above it's neighboring Cores.

In an agreement with Intel, temperature monitoring utilities that are packaged with motherboards show CPU temperature (Tcase) only. Temperature monitoring utilities that are freeware downloads such as Core Temp, Real Temp, RM Clock, OCCT and TAT show Core temperatures (Tjunction) only. Others such as Hardware Monitor, Everest and SpeedFan show both CPU temperature AND Core temperatures. Of these utilities, only SpeedFan can be calibrated for both temperatures.

So... which temperature monitoring utility are you running? Regardless, if you prefer to keep your current BIOS update, then you can use the Calibration Section in the Temp Guide to fine-tune SpeedFan temperatures to your rig.


Hope this helps,

Comp :sol:
 
Wow, thanks for that, Comp. Going to try and be more specific from now on with the temps :)

@Lupiron, Core Temp 0.98.1 shows the same temps as I said above, both cores at 47-48 C on idle. I have an E6600 with revision B2. Is there a problem with one of the revisions that I don't know about?
 
Don't mind Lupi... I think he's got a VID fetish. :pt1cable: The E6600 has only one stepping, which is B2. More from the Guide:

Section 6: Scale

Scale 5: Duo
E6x00: Tcase Max 60c, Stepping B2

-Tcase/Tjunction-
--60--/--65--65-- Hot
--55--/--60--60-- Warm
--50--/--55--55-- Safe
--25--/--30--30-- Cool

Comp :sol:
 
The recent version of Core Temp may be reading your Tjmax at 100C, whereas previous versions of Core Temp read Tjmax at 85C, resulting in the 15 degree difference you are seeing.

You may want to download the Real Temp program found HERE, and use it to measure your temps.

I have found that with controversial processors, which includes your B2 E6600, that this program is more accurate and believable, since the temps you are currently reading are extremely high for an E6600, especially for a decent aftermarket cooler.
 
This version of Core Temp shows my Tj. Max at 85C. I might try and reseat the CPU with some new arctic silver, but I'm not sure that it will do much. Can't hurt to try, except that it's such a pain to remove this cooler given the case I'm using.

I forget what I'm supposed to clean the old paste off with. I heard rubbing alcohol? They only have alcohol with salicylic acid in it here, hope that's okay. I also read something else around here, some magic liquid. Can't remember what it was, tomato juice? Lemon juice? A Bloody Mary???