Core I7 920 CPU cooling issues

[johnh6789]

Hello All,

I am somewhat of a novice when it comes to computers and am having a bit of trouble on my first build in quite some time. My components are as follows:

-Core I7 920 (stock HSF)

-Asus P6T WS mobo

-EVGA 9800 GX2

-6GB Corsair DDR3 1600

- Vista 64 home premium

When I first got the computer running ( two months ago) I was getting idle readings as high as 53 with mid 60's under load, which I thought was high; so I tried installing a sunbeam 120 mm core contact freezer but didnt realize I needed a mount for the sockect 1366.
So I sent it back and decided to use the stock until something specificaly designed for my cpu came out. But now I am getting much higher temp readings since I uninstalled and reinstalled the old HSF to try to put this new one in. I use PC probe (from the mobo support disc) to monitor temps and have been getting readings as high 82 Degrees Celcius (the alert monitor comes on at 77). So things are even worse now. I found out now that they make an adapter for the 1366 to make certain heat sinks work and have become interested in the ZALMAN 9900 http://www.zalman.com/ENG/product/Product_Read.asp?idx=333

But would like some tips on proper seating and use of thermal grease (since obviously I did something wrong when I re-installed my HSF)? Also does anyone know what the safe operatig temp range is and when (or IF I should say lol) I get into a safe temp if I should even consider overclocking? and what would be the best way to go about doing this?

Thank All for any help in advance!

 

[johnh6789]

Also, Is therea specific way I should clean the old thermal grease off as I am afraid I may have used too much when I reinstalled? Should I just use a paper towel?

Also, the case itself is a cooler master HAF full tower with plenty of space and ventilation so I don't think that's an issue.

 

[johnh6789]

Went ahead and bought this one:

XIGMATEK HDT-S1283 120mm Rifle CPU Cooler - Retail

with the I7 bracket for 9.99 additional. Will let everyone know how it works

 

[johnh6789]

Hey all,

Been about two months since I put this one and have been getting temps no higher than 50c under heavy load and 42-44c idle temps. Installation was a breeze with the case I have because the MOBO tray has a cut out right behind the cpu mount which the bracket fits into perfectly! Strange is that my mobo temps (according to PC probe are higher now), by about 3-4c. Figured I would let efveryone know

 

[one-shot]

Hey all,

Been about two months since I put this one and have been getting temps no higher than 50c under heavy load and 42-44c idle temps. Installation was a breeze with the case I have because the MOBO tray has a cut out right behind the cpu mount which the bracket fits into perfectly! Strange is that my mobo temps (according to PC probe are higher now), by about 3-4c. Figured I would let efveryone know

I have the same cooler and it is great. I just ran 21+ hours of OCCT to test my overclock of 3.6GHz @ 1.3Vcore in BIOS. My temps never went above 68 with HT off. I also replaced the factory fan with a higher CFM fan. I've been using a Sycthe Ultra Kaze 3K @ 1450RPM on my Xiggy since last year and it works very well.

 

[johnh6789]

thanks! Ill have to give that fan upgrade a shot since I would like to get the temp a biot lower. Any suggestions on how to get the motherboard temps down? Only after heavy load does the cpu temp go higher than the motherboard which just seems strange.

 

[CompuTronix]

johnh6789,

This thread is 4 1/2 months old! You're just now getting around to replying from June 7th??? I guess you don't earn a living as a fireman!

 

[johnh6789]

lol! the mobo temp issue was on the back burner this whole time I definently don't make my living a fire fighter. In my defense I was on two back to back trips (one into the sagre de cristo natl. forrest w/ no internet) and then started a brutal 18 credit semester. Very true though hehe

 

[CompuTronix]

... does anyone know what the safe operating temp range is ...

OK, here's what you need to know:

Temperatures and overclocking are all about specifications, so it's very important to be specific. If we're not, then the topic makes about as much sense as comparing apples-to-oranges thermal fruit salad in a blender! My objective is to assure that enthusiasts understand Intel's specifications, standards and test methods, so they can better decide how to apply and manage their overclocking options.

From Intel's Processor Spec Finder - http://processorfinder.intel.com/List.aspx?ParentRadio=All&ProcFam=3052&SearchKey=

All Core i7 9xx variants:

Vcore Max 1.375v
Tcase Max (CPU temperature) 68c
Tjunction (Core temperature) 73c

From the Core i7 and Core 2 Temperature Guide - http://www.tomshardware.com/forum/221745-29-sticky-core-core-temperature-guide


"Section 1: Introduction

Core i and Core 2 processors have 2 different types of temperature sensors; a CPU case (not computer case) Thermal Diode centered under the Cores, and Digital Thermal Sensors located on each Core. The case Thermal Diode measures Tcase (Temperature case), which is CPU temperature, and the Digital Thermal Sensors measure Tjunction (Temperature junction), which is Core temperature. Since these sensors measure 2 distinct thermal levels, there is a 5c temperature difference between them, which is Tcase to Tjunction Gradient. Core i7’s / i5’s and Core 2 Quad’s have 1 Tcase and 4 Tjunction sensors, while Core 2 Duo's have 1 Tcase and 2 Tjunction sensors ...

... The monitoring utilities provided by motherboard manufacturers monitor CPU temperature, while some popular freeware utilities monitor Core temperatures ... Real Temp ... is recommended for users interested in monitoring Core temperatures only ... SpeedFan monitors Tcase (CPU temperature) and Tjunction (Core temperature) ... "


The Thermal Specification shown in Intel's Processor Spec Finder is Tcase Max (CPU) not Tjunction (Core), which is a very common misconception among most enthusiasts. Since there's a 5c gradient between the CPU sensor and the Core sensors, (shown in the following Intel document) - http://arxiv.org/ftp/arxiv/papers/0709/0709.1861.pdf - just add 5c to the value shown in the Spec Finder to determine the corresponding Core temperature, which is 73c for all Core i7 9xx variants.

Intel's second and frequently misunderstood Thermal Specification, Tjunction Max, (100c for all Core i7 9xx variants) applies to overtemp protection such as Throttle and Shutdown, so you don't toast your transistors. As such, any i7 9xx Core temperatures which exceed 73c should be considered "overtemp". Further, when specifications are exceeded, then processor degradation becomes a concern, which is explained in the following AnandTech article - http://anandtech.com/cpuchipsets/intel/showdoc.aspx?i=3251&p=6

Prime95 Small FFT's is the Standard for processor thermal testing, because it's a steady-state 100% workload which yields steady-state temperatures, whereas Blend is a memory cyclic workload which yields fluctuating processor temperatures. Small FFT's will reach 97% thermal saturation within 7 to 8 minutes, so a 10 minute test is adequate. Thermal testing should be conducted as close as possible to 22c (72f) Standard ambient, with case covers removed, the computer clear of any desk enclosures, and all fans at 100% RPM to eliminate cooling variables, and to produce consistent and repeatable results for comparisons. If the Gradient between CPU temperature and "mean" (average) Core temperature is not ~ 5c, then BIOS is incorrectly coded. CPU temperature and Core temperatures can be individually calibrated in SpeedFan by following the Calibrations Section in the Temperature Guide.

OCCT and Burn Test (reminiscent of TAT) use LinPack, which shows thermal signatures that resemble the ups and downs of a bad day on the stock market, and cycle between light workloads, through test segments which spray all processor registers with all one's, (100% thermal load = 115% workload), and can push an overclocked i7 9xx with HT enabled at Vcore Max 1.375, right on past Tcase Max to ring the Tjunction Max bell like a fire alarm!

Since there are very few applications or games that will spike, let alone sustain processor workloads beyond 70% to 85%, utilities which load all registers with all one's are not representative of real-world computing. While these utilities are certainly very useful for stability testing, they are inappropriate for thermal testing. The 3DMark benches are excellent for stability testing, as are applications for ripping and encoding.

To make sense of CPU temperature and Core temperature, compare them to a 4 cylinder car with 5 temperature guages; 4 of the guages are cyclinder head temperatures (closest to the heat source), and the 5th guage is the overall engine temperature, which is 5c lower than the other guages, and is the temperature guage with which we're all familiar. We know the red zone (hot) for the i7 9xx starts at 68c (Tcase Max) on the engine temp guage and 73c (Tjunction) on the cylinder head temp guages, but if we push the engine too hard and peg all the guages, (95c Tcase overtemp / 100c Tjunction Max) then the engine will shut down.

If you'd like to learn more about processor temperatures, then just click on the link in my signature.

Hope this helps,

Comp

 

[johnh6789]

Wow!

Quite an elaborate post! In PC probe I get a reading for motherboard and for cpu, so I suspect motherboard would be the core? I made an assumption that "motherboard temp" was some sort of reading of the motherboard in various places to get an idea of where the temp is inside youre case (hence why I was baffled by higher reading on the mobo at times).

I know PC probe isn't the most accurate and I do go to the BIOS when I am concerned about what PC probe shows. But, I don't have any recollectrion of there being a specific reading in the bios of the core temp. (just on for CPU temp). I could be wrong but that definently shed some light on the confusion (makes alot more sense that the CPR would be hotter @ the core and cooler on the case than mobo itself being hotter than cpu). I probably should check to see if there has been a bios revision b/c they definitely aren't 5c difference (only at a worst case and sometimes "motherboard" reading is lower).

Incidentally I had temps seem a bit stranger after I did an RMA for the motherboard b/c the first 2 DIMM slots had a bad ground. I wonder if the replacement they sent has the latest BIOS version

 

[CompuTronix]

I'll make this unmistakably clear; when we discuss processors temperatures, we use the term "Tcase", which refers to the temperature of the entire processor "case" or package, which you removed from Intel's retail box, and installed in the socket on the motherboard. Tcase also means CPU temperature. Tcase has absolutely nothing to do with a computer "case" or a motherboard.

BIOS can not read Core temperatures, nor can PC Probe II. Hardware Monitor reads CPU temperature (Tcase) and Core temperature (Tjunction), but can't be calibrated. SpeedFan reads CPU temperature (Tcase) and Core temperature (Tjunction), and can be calibrated. Core Temp and Real Temp read Core temperatures only, and can also be calibrated.

Other temperatures such as motherboard, northbridge and southbridge have nothing to do with CPU temperature and Core temperatures. The 5c gradient refers to the thermal relationship between CPU temperature and Core temperature only, which can be seen on a calibrated system, such as in the following:

Shown above is idle, then 10 minutes at 100% workload with Prime95 Small FFT's, then idle. Note the 5c Gradient between the CPU and the Cores.