CPU core temps seem high

al360ex

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Hello,

I recently built a new rig for my brother, and I find the CPU temps to be quite high (I mean those on the cores). So, I've got a i7 920 D0 (HT enabled and all power saving disabled) at 4.2GHz (200x21). At idle CPU-Z says my vcore is at 1.288. While stressed, it oscillates between 1.288v and 1.296v.
I ran IBT for 5 hours without problem at the maximum setting.

I've got a Corsair H70 in an exhaust push/pull configuration using 2 Noctua NF-P14FLX. At idle, using RealTemp, it usually sits between 40-45°C. When stressed with Intel Burn Test, after five passes at the maximum setting, the max temp I observe is 89°C. I know my pump works well, it says 1442RPM. My 2 NF-P14 are at 1200RPM and the max exhaust temp I saw was 36.5°C. The intake (ambient) was 20.5°C.

I didn't replace the original TIM...so might that be why I have high temps ? But from what I had heard, the one that came pre-applied was quite good.
I usually use a custom water-cooling loop...so I don't know what temps I'm supposed to have for this overclock (and that CPU cooler) on Air. I looked over reviews and all, but some of them didn't make sense, like this one : http://www.hardocp.com/article/2010/09/28/corsair_h70_water_cooler_performance_testing/3
How can they obtain a max temp of 42.1°C with the H70 while stressing (Prime95) the CPU (vcore of 1.45v and the i7 920 @ 3.6GHz)?

Are my temperatures okay ? Or have I done something wrong ?

Thanks for the help,
al360ex
 
Solution
Remember, voltage is the biggest contributor to OC'ing temp increase.

The H70 'should' be able to keep up with that, esp with push/pull..and the fact that it appears to be mounted externally is another plus. Also guessing it is a new build/cooler so dust build-up isn't a factor.

I'd look for some OC'ing threads for the i7 to see if they can help you make some good manual OC BIOS settings. This is by far the best way to OC...not using the % increase in BIOS or worse...GUI software. Set all your stuff to AUTO, and work on your multiplier/FSB/RAM to get where you want, then start adjusting your voltages as low as you can to be stable for the clocks you want to run.

abully

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first of all try to get to your OC with manual vcore entry... try a stable one under load at the lowest possible vcore...

H70 should be able to cool... what case are you using and what is the fan configuration (including the radiator fans)... the noctua fans are pretty good ones but for the radiator should have gone for high cfm fan (alobeit more noisy) like ultra kaze... the corsair rads' fins are densely packed so you need a lotta penetration with your fans...

Replacing TIM might work... if you have the $ go for IC Diamond 7 Carat Thermal Compound... heard its good...

sub 80 under load will be OK which translates to around 70 under normal load operations...
 

al360ex

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My vcore is set manually to 1.28750 in the BIOS. It shows 1.288 in the operating system (with CPU-Z) and oscillates between 1.288 and 1.296 under load.

As for the case/fans

Case : Cooler Master HAF X
Fans :
4xCooler Master MegaFlow 200mm RED LED
1xNoctua NF-S12B FLX 120mm (for the VGA duct)
2xNoctua NF-P14 FLX 140mm (for the H70)
1xCoolermaster R4-SPS-20AK-GP 80mm (For the VGA bracket)
2xFans that came with the H70 120mm (installed in the swap bay with tie-raps, at 1600rpm).

The NF-P14 have a higher CFM than those that came with the H70, and higher static pressure. Plus, it's used in the NH-D14, which as a very dense heatsink.
 

abully

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I own a NH D14 but its nowhere as dense as the corsair and definitely thinner than the H70 rad... are you using the rad's fans as an intake or exhaust??? using it as an intake will probably be better as it will take cool air from outside and blow it over the rads...

when you set manual Vcore then its not supposed to oscillate... there is some power saving feature which you might not have disabled yet... do that and check till you get a single Vcore reading all-round...
 

al360ex

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I use them as exhaust...But it would make no difference if I used it as intake. My ambient temp (intake) is 21°C. At the exhaust (behind the H70) it's 36°C. Inside the case, just before the H70, the temp is of 23°C. So which fans would you recommend ?


As for my changing vcore...I'll look into it. I might have forgotten a setting somewhere. The motherboard's an Asus Rampage III Formula...and there's just too much options !

 

rubix_1011

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Remember, voltage is the biggest contributor to OC'ing temp increase.

The H70 'should' be able to keep up with that, esp with push/pull..and the fact that it appears to be mounted externally is another plus. Also guessing it is a new build/cooler so dust build-up isn't a factor.

I'd look for some OC'ing threads for the i7 to see if they can help you make some good manual OC BIOS settings. This is by far the best way to OC...not using the % increase in BIOS or worse...GUI software. Set all your stuff to AUTO, and work on your multiplier/FSB/RAM to get where you want, then start adjusting your voltages as low as you can to be stable for the clocks you want to run.

 
Solution

abully

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Since you have already got the noctuas (damn they are expensive!!!), unless you have a lotta $ to burn, i would suggest stick with them and work with the Vcore... some of the best radiator fans are Sanyo Denki San Ace H101, Scythe Ultra Kaze (both 38mm thick)

Scythe S-Flex SFF21G is also a high CFM fan as well as being quiet... by the way the noctuas you have right now are 140mm so they offer greater airflow... only wish they were higher rpm's as well...

I wish other could point out better fans for the rads...
 

al360ex

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Money is not a problem. I could always re-use them in one of my own rigs. The one I built for my brother has got a Scythe Kaze Master Pro 6 channel fan controller, so noise is not really a problem.

I was thinking of maybe this one : http://www.newegg.ca/Product/Product.aspx?Item=N82E16835213001
Is it a good idea ? Or should I go with a more silent one, albeit with a smaller static pressure ?

I also heard that this fan was very good for radiators.

And finally what about this one : http://www.newegg.ca/Product/Product.aspx?Item=N82E16835185054 ?

Thanks for your advice !
 

al360ex

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I've already done that...The only thing I seem to have missed is an option that automaticly ups the vcore under load...When I get home, I'll try to find where it is and disable it...I'm already running stable at 1.296. If I succeed in droping it to 1.28750, do you think I'd see a significant temperature drop ?

Thanks !
 

abully

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Ultra kaze (the last you referred) is the best in terms of noise to cfm... delta is very loud but blows more... scythe flex is a better rad fan than the gentle typhoons...

my suggestion - go with the ultra kaze and control the speed through the fan controller...
 
1. Yes, I'd say a new application of TIM would go a long way. Here's the top performers that don't have curing time issues:

Shin-Etsu MicroSi G751 - Sold at NewEgg under the Masscool brand
Gelid GC-Extreme - Sold at FrozenCPU.
Tuniq TX-3 - Sold at FrozenCPU.

2. If ya use AS5 or any of the repackaged names it's sold under, be advised of the curing time issues listed on their website.

3. Don't expect performance at the top end of the best air coolers with these "faux water coolers". The H70 (manufactured by Asetek) is not all that great a cooler when stacked . Here's some recent test results with the Delta AFC1212D fan where it was compared with the Antec Kuhler 620, several other similar water designs and 2 higher end air coolers.

Thermaltake Jing 69.7 +11.0
Corsair H50 68.1 +9.4
Coolit Vantage A.L.C. 67.8 +9.1
Corsair H70 64.7 +6.0
Coolit ECO A.L.C. 64.3 +5.6
Cooler Master V6 GT 59.5 +0.8
Prolimatech Super Mega 59.4 +0.7
Antec Kühler H2O 620 58.7 +0.0
Thermalright Venomous X 58.0 -0.7

In the table, it shows that the Venemous X had a temp rise of 58C under load testing which was 0.7C better than the Antec Kuhler 620 (also made by Asetek). The Corsair H70 rose 64.7C under testing which was 6C higher then the Kuhler 620....or 6.7, 5.3 and 5.2 degress C worse than the 3 well known air coolers in the test