Does a 4c CPU use twice the power of a 2c?

[janas19]

Under load? How does the power draw of a CPU with four cores compare to a CPU with two cores?

 

[Tsumi]

Depends on which dual cores and which quad cores you're talking about, and what clock speeds as well.

Not to mention, CPU power consumption isn't everything, there's also RAM, motherboard, hard drives, fans, etc.

So a quad-core system will definitely not use twice the power of a dual-core system, given that the dual-core and quad-core are at the same speeds and are of the same architecture, with the rest of the system being the same.

 

[janas19]

Depends on which dual cores and which quad cores you're talking about, and what clock speeds as well.

Not to mention, CPU power consumption isn't everything, there's also RAM, motherboard, hard drives, fans, etc.

So a quad-core system will definitely not use twice the power of a dual-core system, given that the dual-core and quad-core are at the same speeds and are of the same architecture, with the rest of the system being the same.

Thanks for the reply. I'm thinking about the power draw of an i3 processor vs an i5-3550S or T. Strictly looking at the CPU, not the system, and I'm wondering how much more power draw I'd have to consider in a PSU.

My understanding is that Intel's TDP rating isn't meant for power draw, it's intended to give a rating for the amount of heat necessary to dissipate, ie the cooling factor. So in regards to cooling, according to Intel an i3 and an i5-3550S/T would require roughly the same cooling. But that doesn't tell me about power draw on the PSU side, does it?

 

[Tsumi]

You should worry about the power consumption of your entire system rather than just the processor.

An i3 has hyperthreading, and the i5 doesn't. Therefore the i5 won't use double the power even if they were at the same clock speeds. An i7 might use double the power at the same clock speeds, but there's so many variables involved that it's hard to say for sure in all situations.

 

[janas19]

You should worry about the power consumption of your entire system rather than just the processor.

An i3 has hyperthreading, and the i5 doesn't. Therefore the i5 won't use double the power even if they were at the same clock speeds. An i7 might use double the power at the same clock speeds, but there's so many variables involved that it's hard to say for sure in all situations.

I understand the first point.

I guess you did answer my question, which was would the four core use twice the power of the two core? And because of the Hyperthreading and other variables, the answer would be no.

I suppose what I'm really looking for is real world numbers of an i3 vs an i5 power draw when using a benchmark test.

 

[dragonstongue]

all depends on the efficeny of the design, and like mentioned a lot of other factors to take into account, lower voltage ram, a lower draw or more efficient motherboard(usually more phases etc)
http://www.cpu-world.com/CPUs/K8/AM...6400IAA6CZ (ADX6400CZBOX - ADX6400CZWOF).html
http://www.cpu-world.com/CPUs/K10/AMD-Athlon II X4 638 - AD638XOJZ43GX (AD638XOJGXBOX).html

The S variant and the T variant you reference are S is lower then normal for a quad but also usually lower clocked as well(lower leakage) T is even more drastic intel says
S processors feature lower-than-normal TDP (65W on 4-core models).
T processors feature an even lower TDP (45W on 4-core models or 35W on 2-core models).

So yeh it really depends, does power draw double, not exactly cause some parts of the cpu are used be it a dual core or a quad core(given the same "family" or architecture) the ones that are more inefficient by and large are the ones using hyper threading as they do tend to get hotter on average as well as just generally not as efficient though with a program that scales with HT then it is possible the work gets done faster so the cpu downclocks more often or at least does not have to run full bore on all of its cores.

Generally, a more powerfull cpu that is not tapped out nearly as hard cause it is more efficient, faster, able to do its work easier will on average use less power then a older or lower clocked chip, lots of factors.

 

[DejaWiz]

From the same generation, no. Since all processors have things like IMC, peripheral interconnect controller, cache, IGP (if used), etc. All of those things consume power and generate heat separately from the cores regardless of the number of actual processing cores.

So, in essence, going from a dual core i3 to a quad core i5 would not realize double the power draw. Going from a dual core i3 with HT'ing to a quad core i7 with HT'ing may do so, especially with the significantly larger cache in the i7.

This is in regards to a full 100% load scenario for an extended period of time on said processors.