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salatji

Does a CPU use more voltage/power when in idle?

It is not actually using more power when idle, the voltage is higher, yes, but the actual power draw is less. The reason the voltage is lower when running under load is because there is voltage drop due to the increased power draw. Most motherboards have LLC (Load-Line Calibration) settings to try and combat this since it can sometimes cause instability when overclocking very far.

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Posted · Original PosterOP

When under load my CPU seems to use like 1.33ish volts. In idle he fluctuates between 1.38 and 1.42. I haven't overclocked it or anything.

 

Is this normal behaviour? It feels weird to me that it should use a lot more voltage when it has nothing to do...

ingame.png

idle.png

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1 minute ago, WereCat said:

That's normal. 

Depends on the power profile set in windows. Is this the balanced profile? If yes then C states is disabled in BIOS


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It does use more, since when cpu running single core its getting more vols, and since in idle my 8 core cpu only has 6 cores enabled, so i hvae higher voltage.

But in stress testing the 8 cores are being used and the voltage is being outputted to the all 8 cores, not only to the 6 cores

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Posted · Best Answer

It is not actually using more power when idle, the voltage is higher, yes, but the actual power draw is less. The reason the voltage is lower when running under load is because there is voltage drop due to the increased power draw. Most motherboards have LLC (Load-Line Calibration) settings to try and combat this since it can sometimes cause instability when overclocking very far.


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Posted · Original PosterOP

Ah... ok. I was a bit curious if I should then overclock my CPU to reduce power draw, but if only voltage is higher then I probably will OC it anyway, but not for energy efficiency :D

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30 minutes ago, Husky said:

The reason the voltage is lower when running under load is because there is voltage drop due to the increased power draw. Most motherboards have LLC (Load-Line Calibration) settings to try and combat this since it can sometimes cause instability when overclocking very far.

Voltage droop from loading isn't the main factor at stock. There's a curve of voltage needed at a given clock. When a single core is loaded, which can include light loads, the CPU will boost right up. At higher clocks, it needs higher voltage. When multiple cores are loaded, the boost is less and the lower clock needs a lower voltage.

 

If you were running fixed clock and voltage like you would in a manual overclock, then the drop with more cores loaded is from loading.


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5 hours ago, salatji said:

When under load my CPU seems to use like 1.33ish volts. In idle he fluctuates between 1.38 and 1.42. I haven't overclocked it or anything.

 

Is this normal behaviour? It feels weird to me that it should use a lot more voltage when it has nothing to do...

ingame.png

idle.png

Where is the CPU Voltage in this screenshot?  I don't see it anywhere.

You have VID shown, however VID is not equal to vcore as VID is a hardwired value that is influenced by several factors and is a CPU request value.

Make sure you have the Vcore sensors showing.  If this is a Gigabyte board, look for VR VOUT, which is even more accurate!

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19 hours ago, porina said:

Voltage droop from loading isn't the main factor at stock. There's a curve of voltage needed at a given clock. When a single core is loaded, which can include light loads, the CPU will boost right up. At higher clocks, it needs higher voltage. When multiple cores are loaded, the boost is less and the lower clock needs a lower voltage.

 

If you were running fixed clock and voltage like you would in a manual overclock, then the drop with more cores loaded is from loading.

Ah ok, I stand corrected. I wasn't thinking outside of manual voltage.


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