E8500: Acceptable Core Temperature Range?

[JackSpadesSI]

My computer is experiencing occasional odd crashing behavior. I booted to MemTest and ran that through 4 cycles successfully, so that is just about the only hardware component of the computer that I can trust.

I also booted the computer with the Vista install disc and ran Start-up Repair, which said there was nothing wrong with my computer.

Now I suspect it may be overheating. I installed SpeedFan on my system to monitor the core temperatures. Can anyone tell me what an acceptable temperature range is for the E8500 (no overclock)?

Let's say the bottom of the range is at idle, and the top of the acceptable range is while running Prime95. My house is rather well air conditioned, so I shouldn't have an external heat issue.

Thanks for the help!

 

[JackSpadesSI]

Oh, P.S. - the computer ran GREAT for the first two months after I built it, but it has been doing this for about 3 weeks now.

 

[BonzaiDuck]

First, my rule-of-thumb may have been superseded by revisions to SpeedFan, but the preferred utilities for reading core temperatures include CoreTemp, RealTemp, HWMonitor and Everest Ultimate. The last of these will show a bias in temperature for a single core, likely due to the fact that it reads and updates all the sensors it can find in the system.

There are two kinds of temperature sensors embedded in the CPU (E8500): a "TCase" sensor, and the sensors for each core. TCase is a legacy sensor that measures temperatures at the center of the (interior-side) of the IHS or processor-cap. Its temperature-readings should lag behind -- or be below -- the core readings by 5 to 10C.

The thermal spec for all the E8x00 cores is around 72C for TCase. That is, Intel recommends cooling solutions that would keep the TCase value at or below that temperature (for reasonable room-ambients) under severe load conditions. And all temperatures you can record from sensors in your hardware are linearly affected by room-ambient or room-temperature.

PRIME95 (multi-core) does not produce the most extreme severe load temperatures, even if it shows processor usage at 100%. The best software to produce the maximum temperatures would be LinPack, also known as IntelBurnTest in one shareware version.

Again, or to clarify, idle temperatures are not as significant as readings taken under load conditions. Further, you need to know this:

Intel had issued a disclaimer about the E8x00 and Q9x50 core sensors, stating that they were not intended to record idle temperature values accurately. If you check this forum over the last year, you will find where many users have discovered that one or more of the core sensors is "stuck" at a value appearing excessive for idle conditions. For instance, my E8600 CPU shows core temperatures at 51C/51C under idle, and the sensor readings only change to exceed those numbers when TCase is approaching 51C.

For these CPUs with defective core sensors, my approach has been to monitor the TCASE sensor instead. Some have suggested RMA'ing the CPUs, but with Intel's disclaimer, many of us do not deem it essential to replace the CPU because of these core-sensor limitations and failings.