Unusually warm E8400 with Xigmatek S1283

[spritemv]

I recently built my first computer and have now decided to OC it. My system is as follows:

CPU: Intel C2D E8400
MEMORY: G.Skill 2x2GB DDR2-1000 SDRAM
MOBO: Asus P5Q
CPU COOLER: Xigmatek HDT-S1283 (with Arctic Silver 5)
PSU: Antec True Power Trio 650W
CASE: Antec P182
GPU: 8800GTS (G92) 512MB
HDD: 2x Samsung SpinPoint P Series 250GB
SOUND: Creative X-Fi Xtreme Music

I'm a little concerned that my temps are unusually high. At stock speeds with the case cover off, I'm getting an idle core temp of 36C (RealTemp). I've read RealTemp is the most accurate for 45nm chips, but other programs have measured my idle temp to be 40C (SpeedFan) and 46C (CoreTemp). 36C wouldn't be horrible, but considering the ambient temp is 23-24C, this seems a bit high. The readings of the other programs scare me a bit.

I've started a Prime95 stress test and my core temp is currently at 47C (RealTemp), 52C (SpeedFan), and 57C (CoreTemp). I'm hoping RealTemp is indeed the most accurate for my chip. It still seems these are very high temps considering I'm running at stock speed. I'm a bit hesitant to begin OCing until I can get my temps down.

I installed both the S1283 and AS5 according to the manufacturer's instructions and am running my CPU fan on high. My cooler feels cool to the touch. Does anyone have any advice? Also, I've heard some of the temp sensors on E8400 chips give false high readings, is there any truth to this?

 

[georgy]

realtemp is the most accurate it's true. What you can do in Coretemp is to set tjmax to 95 (as it should be for this cpu). Your temps are fine if i compare to my e8400 @ 3.6 ghz (idle at 38, load at 53).

 

[Pazuzoo]

My 8400 with the same cooler and paste never passes 44 on speedfan, and that's overclocked to 3.6. I do have decent airflow in my case though.

It's hard to say w/o knowing exactly what's going on inside your case, but it does seem a bit high to me considering those temps sound more like what I was getting on stock cooling at stock settings.

I'm using the bolt thru kit though, perhaps you're using the push pins?

 

[spritemv]

Yep, I'm using push pins.

 

[geofelt]

I think your temperatures are ok. Under load, my system shows 58c. with an ambient of 29c. The cpu will throttle if it gets too hot, so don't worry too much about damaging it.

The push pins can be tricky. Coolers with push pins are best mounted outside of the case so you can verify that all 4 pins are properly through and locked. With your pc powered down, try to rock the cooler a bit to see if it wiggles. If it is on solid, you should be ok.

 

[spritemv]

I did mount the cooler outside my case and it appeared that all 4 pins where locked. The cooler doesn't rock at all now that it's mounted.

 

[spritemv]

I think I can bump my CPU up to 3.6GHz without increasing the voltage. Will a mere bump in FSB increase core temp if I leave the voltage where it is?

 

[CompuTronix]

spritemv,

The following scale applies to your E8400, and is from my Core 2 Quad and Duo Temperature Guide: http://www.tomshardware.com/forum/221745-29-core-quad-temperature-guide

Scale 1: Duo
E7200: Tcase Max 74c, Stepping M0,TDP 65W, Idle 8W
E4700: Tcase Max 73c, Stepping G0, TDP 65W, Idle 8W
E4x00: Tcase Max 73c, Stepping M0, TDP 65W, Idle 8W
E2xx0: Tcase Max 73c, Stepping M0, TDP 65W, Idle 8W
E8x90: Tcase Max 72c, Stepping C0, TDP 65W, Idle 8W
E8x00: Tcase Max 72c, Stepping C0, TDP 65W, Idle 8W
E6x50: Tcase Max 72c, Stepping G0, TDP 65W, Idle 8W
E6540: Tcase Max 72c, Stepping G0, TDP 65W, Idle 8W

-Tcase/Tjunction-
--70--/--75--75-- Hot
--65--/--70--70-- Warm
--60--/--65--65-- Safe
--25--/--30--30-- Cool

CPU temperature is Tcasae, and Core temperature is Tjunction.

You have plenty of headroom for overclocking. Frequency increases temperatures linearly, which is minimal, however, Vcore increases temperatures exponentially, which is immediately obvious. Be certain to use small FFT's when testing temperatures with Prime95 or Orthos, since it provides the heaviest thermal load. Thermal saturation is typically reached within 7 to 8 minutes, so a 10minute test run is sufficient to find maximum processor temperatures.

Don't become too focused on Idle temperatures, because many 45 nanometer processors have Digital Thermal Sensors which won't respond adequately at the lowest Idle temperatures. Use the "Test Sensors" button in Real Temp to determine how responsive your sensors are, then read the Real Temp documentation at Tech Powerup.com to calibrate your Idle temperatures.

If your E8400 sensors are of the fortunate few that are more responsive than most, then at standard ambient 22c using auto settings, a high end-cooler, case covers removed and all fans at 100% RPM, the lowest possible Idle Core temperatures you can expect should be 27c. Linearity problems exist with these sensors, because Intel never intended them to be used for any purpose other than at higher temperatures for thermal protection for Throttle (overtemp conditions) and Shutdown.

The 3rd sensor in your processor, which monitors overall CPU temperature (Tcase), was designed for temperature monitoring from Idle to Load, and is the only temperature that Intel supports, which is shown at Intel's Processor Spec Finder: http://processorfinder.intel.com/details.aspx?sSpec=SLAPL

To understand the differences between CPU temperature and Core temperature, which can both be accurately calibrated using my Temp Guide, click the link in my signature.

I hope this helps to answer your questions.

Comp

 

[spritemv]

Thanks for the advice CompuTronix. I had already read your guide so I was somewhat familiar with the different temperature measurements, but as a first time OC'er, I still have a lot to figure out.

I just pushed my FSB up to 400 which sets me at 3.6GHz. Under load, my CPU peaks at 58C which is still in the safe range.

Other than adjusting the FSB and turning off C1E, I left everything else on AUTO. Should I keep the C1E off? Are there any other tweaks I can make that won't push my temps up too much? At 3.6GHz am I even benefiting by using my DDR2-1000 ram over the 800 MHz variety? Do I need to adjust the DRAM Frequency or anything? Sorry for all the questions and thanks in advance!