[SOLVED] I5 3470 uses 40w of power under load

Jul 4, 2019
34
0
30
0
is it bad that my i5 3470 only uses 30-40 watts of power under full load stressed and gaming i havent seen it go higher than 40.
 

CompuTronix

Judicious
Moderator
is it bad that my i5 3470 only uses 30-40 watts of power under full load stressed and gaming i havent seen it go higher than 40.
Jarebear,

In a word, no. What you're seeing is normal. However, since power consumption is driven by load which is a HUGE variable, please define what software you were using for "full load stressed".

Here's why:

Intel tests their processors using a steady 100% TDP workload. "Full load" is a popular but non-specific user term which could mean anything. Games, apps, streaming, rendering, transcoding and most utilities have partial, fluctuating workloads which are poorly suited for testing power consumption and thermal performance.

“Stress” tests vary widely and can be characterized into two categories; fluctuating workloads and steady workloads. Prime95 Small FFT's (no AVX) is ideally suited for testing power consumption and thermal performance, because it conforms to Intel's datasheets as a steady 100% workload. No other utility can so closely replicate Intel's power and thermal test workload.



When testing power consumption and thermal performance, it's crucial to run utilities that don't overload or underload your processor. 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.

Shown below from left to right: Prime95 Small FFT's, Prime95 Blend, Linpack and IntelBurn Test.



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

About TDP: Measured TDP (power consumption in watts) may vary from rated TDP. Specifications are based on the fastest Hyper-Threaded (flagship) variants for X-Series, Extreme, i9's, i7's, i3's and recent Pentiums. Slower processors without Hyper-Threading such as i5's and some earlier Pentiums and Celerons may not reach TDP. The key word in "Thermal Design Power" is Design.

For example, the 3rd generation low-end i5-3330 shares the same design as the flagship i7-3770K, which are both rated at 77 Watts TDP. But since the i5's base clock is 500MHz slower and doesn't have hyper-threading, it consumes less power and therefore doesn't reach TDP. Likewise, since your mid-range i5-3470 also shares the same design as the i7-3770K, but doesn't have hyper-threading, it doesn't reach TDP either.

This means when the fastest Hyper-Threaded (flagship) variants run Prime95 Small FFT’s (without AVX), the processors should show steady power consumption (watts) and core temperatures generally within +/- a few % of TDP at stock settings. Accordingly, Prime95 Small FFT’s (without AVX) conforms to Intel's datasheets as a valid 100% workload.



About AVX: Advanced Vector Extension (AVX) Instruction Sets were introduced with Core i 2nd generation CPU’s, then AVX2 with 4th generation and AVX-512 with later generations of High End Desktop (HEDT) CPU’s as in certain X-Series, Extreme, i9’s and i7’s. Prime95 versions with AVX/2/512 enabled impose an unrealistic 130% workload which can adversely affect stability and severely overload your CPU. 2nd and 3rd generations are less affected, but core temperatures on 4th through 9th generations may be over 20°C higher.

Since your 3rd generation i5-3470 does not have AVX2 or AVX-512 Instruction Sets, it's only affected by the original AVX Instruction Set, which has a lesser adverse effect on stability, power consumption and core temperatures.

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 power consumption and core temperatures will be the same as 29.8 without AVX, it's easier to just use 29.8. You can also use 26.6 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.

The bottom line is that when testing power consumption and thermal performance, in order to make apples-to-apples comparisons, it's crucial to run the proper utility and specific test that conforms to Intel's datasheets. This means the utility of choice is Prime95 v28.9 Small FFT's with all AVX test selections disabled.

CT :sol:
 

CompuTronix

Judicious
Moderator
is it bad that my i5 3470 only uses 30-40 watts of power under full load stressed and gaming i havent seen it go higher than 40.
Jarebear,

In a word, no. What you're seeing is normal. However, since power consumption is driven by load which is a HUGE variable, please define what software you were using for "full load stressed".

Here's why:

Intel tests their processors using a steady 100% TDP workload. "Full load" is a popular but non-specific user term which could mean anything. Games, apps, streaming, rendering, transcoding and most utilities have partial, fluctuating workloads which are poorly suited for testing power consumption and thermal performance.

“Stress” tests vary widely and can be characterized into two categories; fluctuating workloads and steady workloads. Prime95 Small FFT's (no AVX) is ideally suited for testing power consumption and thermal performance, because it conforms to Intel's datasheets as a steady 100% workload. No other utility can so closely replicate Intel's power and thermal test workload.



When testing power consumption and thermal performance, it's crucial to run utilities that don't overload or underload your processor. 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.

Shown below from left to right: Prime95 Small FFT's, Prime95 Blend, Linpack and IntelBurn Test.



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

About TDP: Measured TDP (power consumption in watts) may vary from rated TDP. Specifications are based on the fastest Hyper-Threaded (flagship) variants for X-Series, Extreme, i9's, i7's, i3's and recent Pentiums. Slower processors without Hyper-Threading such as i5's and some earlier Pentiums and Celerons may not reach TDP. The key word in "Thermal Design Power" is Design.

For example, the 3rd generation low-end i5-3330 shares the same design as the flagship i7-3770K, which are both rated at 77 Watts TDP. But since the i5's base clock is 500MHz slower and doesn't have hyper-threading, it consumes less power and therefore doesn't reach TDP. Likewise, since your mid-range i5-3470 also shares the same design as the i7-3770K, but doesn't have hyper-threading, it doesn't reach TDP either.

This means when the fastest Hyper-Threaded (flagship) variants run Prime95 Small FFT’s (without AVX), the processors should show steady power consumption (watts) and core temperatures generally within +/- a few % of TDP at stock settings. Accordingly, Prime95 Small FFT’s (without AVX) conforms to Intel's datasheets as a valid 100% workload.



About AVX: Advanced Vector Extension (AVX) Instruction Sets were introduced with Core i 2nd generation CPU’s, then AVX2 with 4th generation and AVX-512 with later generations of High End Desktop (HEDT) CPU’s as in certain X-Series, Extreme, i9’s and i7’s. Prime95 versions with AVX/2/512 enabled impose an unrealistic 130% workload which can adversely affect stability and severely overload your CPU. 2nd and 3rd generations are less affected, but core temperatures on 4th through 9th generations may be over 20°C higher.

Since your 3rd generation i5-3470 does not have AVX2 or AVX-512 Instruction Sets, it's only affected by the original AVX Instruction Set, which has a lesser adverse effect on stability, power consumption and core temperatures.

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 power consumption and core temperatures will be the same as 29.8 without AVX, it's easier to just use 29.8. You can also use 26.6 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.

The bottom line is that when testing power consumption and thermal performance, in order to make apples-to-apples comparisons, it's crucial to run the proper utility and specific test that conforms to Intel's datasheets. This means the utility of choice is Prime95 v28.9 Small FFT's with all AVX test selections disabled.

CT :sol:
 

ASK THE COMMUNITY

TRENDING THREADS