Guys,
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 % of TDP, averaged across six processor Generations at stock settings rounded to the nearest 5%:
Although these tests range from
70% to 130% TDP workload, Windows Task Manager interprets every test as
100% CPU Utilization, which is processor resource activity,
not actual workload. Core temperatures respond directly to Power consumption (Watts), which is driven by workload. Prime95 v29.8 Small FFT’s
(AVX disabled) provides a
steady 100% workload
, even when TDP is exceeded by overclocking. If Core temperatures don't exceed
85°C, your CPU should run the most demanding
real-world apps without overheating.
• AVX - Advanced Vector Extension (AVX) Instruction Sets were introduced with Core i 2nd Generation CPU’s, then AVX2 with 4th Generation and AVX512 with later Generations of High End Desktop (HEDT) CPU’s as in certain X-Series, Extreme, i9’s and i7’s.
Running versions of Prime95 with AVX enabled imposes an unrealistic workload which can adversely affect stability and severely overload your CPU to 130% TDP. 2nd and 3rd Generations are less affected, but Core temperatures on 4th through 9th Generations may be
over 20°C higher.
Many 6th through 9th Generation motherboards address the AVX problem by providing “offset” adjustments (downclock) in BIOS. -3 (300 MHz) or more may be needed to limit Core temperatures to
85°C. Since 4th and 5th Generations don’t have AVX offsets, you can create individual BIOS Profiles for AVX and non-AVX software. Except for a few utilities and specialized computational apps,
AVX intensive real-world apps (rendering, transcoding) and recent games with AVX shouldn’t exceed Prime95's test workload without AVX.
As per Intel’s Datasheets, TDP and Thermal Specifications are validated “without AVX”. In Prime95 versions from 27.7 through 29.4, AVX can be
disabled by inserting
CpuSupportsAVX=0 into the
local.txt file, which appears in Prime95's folder after the first run. However, since Core temperatures will be the same as
29.8 without AVX, it's easier to just use 29.8. You can also use v26.6 which doesn't have AVX. Core i 1st Generation, Core 2, Pentium and Celeron processors don't have AVX Instruction Sets, so they're not affected.
See Page 87,
Section 5.1.1 -
Thermal Considerations - first paragraph, second sentence:
8th and 9th Generation Intel® Core™ Processor Families Datasheet, Volume 1 -
https://www.intel.com/content/www/u...core/8th-gen-core-family-datasheet-vol-1.html
• Download the latest version of Prime95, which is 29.8 - https://www.mersenne.org/download/
This version finally provides an easy way to disable AVX, AVX2 and AVX 512 by just clicking on the boxes.
Also see Intel Temperature Guide -
https://forums.tomshardware.com/threads/intel-temperature-guide.1488337/
You might want to read:
Section 11 -
Thermal Test Basics
Section 12 -
Thermal Test 100% Workload
CT 😎