Normal I7 8700k temp

vetlejakob,

Here's the operating range for Core temperature:

Core temperatures above 85°C are not recommended.

Core temperatures below 80°C are preferred.

Core temperatures increase and decrease with Ambient temperature.

Highest Core temperatures occur during stress tests, rendering or transcoding, but are lower during less processor intensive workloads such as applications and gaming. Core temperatures can vary greatly among gaming titles due to differences between CPU and GPU workloads.


Guys,

Concerning Prime95, feelinfroggy777 is correct ... about versions later than 26.6. Later versions are definitely a worst case scenario due to the "AVX" issue, which can force your CPU to run close to 130% workload.

2nd through 8th Generation i3, i5 and i7 CPU's have AVX (Advanced Vector Extension) Instruction Sets. Prime95 versions later than 26.6 run AVX code on the CPU's Floating Point Unit (FPU) which causes unrealistic temperatures up to 20°C higher.

AVX can be disabled in Prime95 versions later than 26.6 by inserting "CpuSupportsAVX=0" into the "local.txt" file in Prime95's folder. However, since Core temperatures will be the same as 26.6, it's easier to just use 26.6. AVX doesn't affect Core i 1st Generation, Core 2, Pentium or Celeron processors since they don't have AVX Instruction Sets.

For the record, Prime 95 v26.6 Small FFT's is ideal for thermal testing.

Ambient temperature, hardware configurations and stress test software are major variables, so in order to compare apples to apples, it's important to be specific. Since idle and load temperatures are relative to ambient temperature, it's an important variable to know. Moreover, “load” or “full load” are just misleading user terms that could mean anything.

Not all loads are created equal. Gaming, applications, rendering, transcoding and streaming are partial, fluctuating workloads with fluctuating temperatures, which aren’t well suited for testing thermal performance.

Intel tests their processors at a steady 100% TDP to validate Thermal Specifications. Prime95 version 26.6 Small FFT's is ideal for CPU thermal testing, because it's a steady 100% workload with steady Core temperatures that typically runs Core i variants with Hyperthreading and Core 2 processors within +/- a few % of TDP. No other utility so closely replicates Intel's test conditions. This is the utility Real Temp uses for testing Core temperature sensors.

Utilities that don't overload or underload your processor will give you a valid thermal baseline. Here’s a comparison of utilities grouped as thermal and stability tests according to approximate % of TDP, averaged across six processor Generations at stock settings.

Take a look:

All tests will show 100% CPU Utilization in Windows Task Manager, which seldom coincides with %TDP workload. Higher TDP tests produce higher Core temperatures. Although actual Power dissipation (Watts) varies with Core Speed, Core voltage, cooling and workload, Prime95 v26.6 Small FFT’s always provides a steady 100% workload, whether you’re running stock or overlocked.

Shown below from left to right: Small FFT's, Blend, Linpack and IntelBurn Test.

Note the steady thermal signature of Small FFT's, which allows accurate measurements of Core temperatures. A steady 100% workload is key for thermal testing so the CPU, cooler, socket, motherboard and voltage regulators can thermally stabilize.

Shown below from left to right: Small FFT's, Intel Extreme Tuning Utility CPU Test, and AIDA64 CPU Test.

Intel Extreme Tuning Utility is also a fluctuating workload. Although AIDA64's CPU test is a steady workload, it's far below TDP, which is insufficient for thermal testing. All other AIDA64 CPU test combinations are fluctuating workloads, which again aren't well suited for thermal testing.

• Thermal testing: Prime95 v26.6 Small FFT's - http://www.mersenneforum.org/showthread.php?t=15504

Asus RealBench runs a realistic AVX workload typically within +/- a few % of TDP, and is an excellent utility for testing overall system stability, whether you're running stock or overclocked. This is the utility Silicon Lottery uses for testing CPU stability.

• Stability testing: Asus RealBench - http://rog.asus.com/rog-pro/realbench-v2-leaderboard/

CT