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[McTraveller]

The power consumed by a CPU (which equals heat dissipated) is given by P = CV²F, where C is capacitance, V is voltage and F is clock speed. If my data (collected on a single CPU, an i5-9300H) is correct, C scales quadratically with F*, and V scales linearly with F*. That would imply that P scales to the fourth power of F... which probably explains why even the best of processors can't go any faster than 5 GHz stock. Even then, you'd need some really good liquid cooling to see such high clock speeds under load.

*The "multiplier" mentioned represents the clock speed. Multiply by 99.8 MHz (the average bus frequency for the CPU tested) to get the actual clock speed.

Edit: But I really think I'm wrong in saying that power scales to the 4th power of clock speed. This chart came from the same data set, and it definitely shows that power grows quadratically with clock speed, not to the 4th power.

Out of curiosity, why not use power = VI?  That's a much simpler measurement and doesn't care about those pesky frequency-dependent things like capacitance.

[methylatedspirit]

The power consumed by a CPU (which equals heat dissipated) is given by P = CV²F, where C is capacitance, V is voltage and F is clock speed. If my data (collected on a single CPU, an i5-9300H) is correct, C scales quadratically with F*, and V scales linearly with F*. That would imply that P scales to the fourth power of F... which probably explains why even the best of processors can't go any faster than 5 GHz stock. Even then, you'd need some really good liquid cooling to see such high clock speeds under load.

*The "multiplier" mentioned represents the clock speed. Multiply by 99.8 MHz (the average bus frequency for the CPU tested) to get the actual clock speed.

Edit: But I really think I'm wrong in saying that power scales to the 4th power of clock speed. This chart came from the same data set, and it definitely shows that power grows quadratically with clock speed, not to the 4th power.

Out of curiosity, why not use power = VI?  That's a much simpler measurement and doesn't care about those pesky frequency-dependent things like capacitance.

It would be so easy if I were able to read the current going through the CPU. Unfortunately, my CPU only gives me its power consumption, voltage and clock frequency. I think there is a sensor for current, since it's possible to set the maximum current the CPU is allowed to draw, but the program I'm using doesn't show it. I then have to derive capacitance from there, which is where the confusion between power being either quadratic or quartic with respect to clock frequency starts.  After looking at the data again, it turns out that voltage actually scales exponentially with clock frequency, but it's so close to being a straight line that I'm assuming that it's linear.

Also, I'm not really concerned about power consumption, I'm more concerned about the heat dissipated by a processor over a range of clock frequencies, given a fixed workload. I need the clock frequency to predict what happens if I were to, say, overclock this processor. (Which I can't, but a man can dream)

[McTraveller]

If your program gives you power consumption - I'm not sure why you need anything else?  Power consumption is "heat generated".  Why don't you just plot reported power consumption versus frequency?  Are you suspecting the reported power consumption is not correct?

[methylatedspirit]

If your program gives you power consumption - I'm not sure why you need anything else?  Power consumption is "heat generated".  Why don't you just plot reported power consumption versus frequency?  Are you suspecting the reported power consumption is not correct?

I undervolted this processor, so I did need to know what would happen if I set the voltage offset on the processor to 0.000V (in other words, reset it back to stock settings) instead of -0.145V, which is the offset I took my measurements at. I decided against setting the offset to 0V for the measurements, since thermal throttling starts to kick in at around 3.7 GHz, and it refuses to run any faster. That, or I don't know what I'm doing, which is equally plausible.

[Kagus]

Y'all haven't read JDatE? Sucks to suck, I guess.   

Why didn't you make it into an acronym?

Still have no idea what's being talked about here.

Is Jdate just a Japanese date? Are there Kdates?

I'm pretty sure Jdate is for Jews.

It is indeed! Because that matters to people.

One of the things found when trying to search for JDatE was an article asking why non-Jews were apparently using Jdate to hook up with hot Jewish singles.

I'm guessing there was a discount or something.

[scriver]

Old Man Henderson is basically the gaming equivalent of JDatE.   

Spoiler (click to show/hide)

What?

OMG I just saw this post because of page skip bug and I mean

This is the best logo I have ever seen

[Iduno]

I've seen better.

[King Zultan]

Y'all haven't read JDatE? Sucks to suck, I guess.   

Why didn't you make it into an acronym?

Still have no idea what's being talked about here.

Apparently its an acronym for John Dies at the End.

[Naturegirl1999]

You know those image captchas where you click on all pictures with an item and submit? The ones that are used to train self driving cars? I want to go to a website where I can do those to help with training AI

[Trekkin]

You know those image captchas where you click on all pictures with an item and submit? The ones that are used to train self driving cars? I want to go to a website where I can do those to help with training AI

Foldit is used for training some neural nets, I think, if you want to do something a little more involved.

[scriver]

My immediate thought was that I too want to go on such a website but to click on every part of the pictures until the AI becomes neurotic and erratic and afraid of everything, just like ne

[methylatedspirit]

In Futurama, exposed mechanical parts of robots are considered titillating to robots. Considering that Bender runs on a 6502 CPU, what would he think of an exposed CPU die, especially that of a 6502? Would he be attracted to it, or would he react like humans looking at their own brains?

[Il Palazzo]

You know those image captchas where you click on all pictures with an item and submit? The ones that are used to train self driving cars? I want to go to a website where I can do those to help with training AI

My immediate thought was that I too want to go on such a website but to click on every part of the pictures until the AI becomes neurotic and erratic and afraid of everything, just like ne

You two better be on a lookout for time travelling bodybuilders trying to prevent the birth of SkyNet.

[scriver]

In Futurama, exposed mechanical parts of robots are considered titillating to robots. Considering that Bender runs on a 6502 CPU, what would he think of an exposed CPU die, especially that of a 6502? Would he be attracted to it, or would he react like humans looking at their own brains?

Depends on how hot it's running

[delphonso]

Ooo, baby. It looks like that CPU is overLOADED!