i5 4690 With Stock Cooler @ 95 Degrees Celsius on Prime95

Guys,

Here's the normal operating range for Core temperature:

80C Hot (100% Load)
75C Warm
70C Warm (Heavy Load)
60C Norm
50C Norm (Medium Load)
40C Norm
30C Cool (Idle)

Core temperatures in the mid 70's are safe.

Midguards,

The issue with Prime95 is strictly version specific.

ArticFox,

Do NOT run any versions of Prime95 later than 26.6. Here's why:

Core i 2nd, 3rd, 4th, 5th and 6th Generation CPU's have AVX (Advanced Vector Extension) instruction sets. Recent versions of Prime95, such as 28.5, run AVX code on the Floating Point Unit (FPU) math coprocessor, which produces unrealistically high temperatures. The FPU test in the utility AIDA64 shows similar results.

Prime95 v26.6 produces temperatures on 3rd, 4th, 5th and 6th Generation processors more consistent with 2nd Generation, which also have AVX instructions, but do not suffer from thermal extremes due to having a soldered Integrated Heat Spreader and a significantly larger Die.

Please download Prime95 version 26.6 - http://windows-downloads-center.blogspot.com/2011/04/prime95-266.html

Run only Small FFT’s for 10 minutes.

Use Real Temp to measure your Core temperatures, as it was developed specifically for Intel processors: Real Temp - http://www.techpowerup.com/downloads/2089/real-temp-3-70/

Your Core temperatures will test 10 to 20C lower with v26.6 than with v28.5.



Tcase is CPU temperature, NOT Core temperature.

Core temperature is 5C higher than CPU temperature. Here's why:

Tcase is measured on the surface of the Integrated Heat Spreader (IHS), which is not in close proximity to the heat sources. Core temperature is measured at the transistor junctions directly on the hot spots inside the Cores, which are the heat sources.

Most of the heat dissipates from the Cores inside the Die through the internal layer of Thermal Interface Material (TIM) to the IHS. Heat then dissipates through the external layer of TIM to the cooler. Some heat also dissipates from the Die to the substrate, package, socket and motherboard.

At 100% workload this causes a 5C thermal gradient from the transistor junctions where Core temperatures are measured, to the surface of the IHS where CPU temperature (Tcase) is measured. A good analogy is that it gets hotter as you get closer to the flame.

Although Tcase for the i5 4690 is 72C, you always need to add 5C to any Tcase specification to get the corresponding Core temperature. Tcase + 5 makes the Core temperature 77C.

The relationship between Core temperature and CPU temperature is not in the Thermal Specifications; it's only found in a few engineering documents. In order to get a clear perspective of processor temperatures, it's important to understand the terminology and specifications.

Please read this Tom’s Sticky: Intel Temperature Guide - http://www.tomshardware.com/forum/id-1800828/intel-temperature-guide.html

Thanks,

CT