Anyone know if the CPU consumption (Watt) is changing ?

[bonzaiholding]

If i have CPU X of company Y and its consume by Watt is 95W , does the consumption in Watt changing throw the process or it allways consume 95W?

 

[GhislainG]

It consumes 95W at 100% CPU utilization. Idle power is much lower.

 

[Shadow703793]

Are you talking about the TDP or the actual power draw?

 

[xaira]

95w=95w the cpu will use max 95w when all its components are pushed to their limits at stock clock

 

[randomizer]

Are you talking about the TDP or the actual power draw?

^This. TDP is not power consumption.

 

[bonzaiholding]

It consumes 95W at 100% CPU utilization. Idle power is much lower.

How much lower?

 

[amdfangirl]

^This. TDP is not power consumption.

TDP is thermal design power or something like that.

It is a worst case scenario of how much a CPU can produce.

 

[Outlander_04]

http://en.wikipedia.org/wiki/Thermal_Design_Power

http://www.silentpcreview.com/article169-page3.html

"What this means is that Intel’s TDP is actually lower than the maximum power dissipation of the processor (and as you’ll see later, it can be significantly lower). This is in stark contrast to AMD’s TDP numbers, which are higher than the respective processor’s maximum power dissipation. "

 

[amnotanoobie]

How much lower?

I think you need to take a look at reviews of processors. Each generation of processor from any company does differ in their power consumption when idle. An example would be an i7 vs a C2Q, an i7 may consume higher when at load, but it is also consumes lower power when idle.

 

[apache_lives]

also bare in mind performance your pulling from that power consumed/emitted etc

 

[jasperjones]

It seems to me that most of the power a CPU draws is converted into heat. I'm just a layman but I would guess that >90% of the power drawn is converted into heat (based on reading stuff like this: http://www.lostcircuits.com/mambo//index.php?option=com_content&task=view&id=44&Itemid=1&limit=1&limitstart=3).

So I'd argue the main reason TDP =/= a CPU's maximum power consumption is that the TDP doesn't measure the theoretically maximum power dissipation of a CPU. Specifically, when TDP is calculated, (i) spikes of power dissipation so short that they are irrelevant for cooling system design are ignored; (ii) code is employed which requires <100% CPU utilization (simply because it's so difficult to generate machine code that makes use of all available units of the CPU at the same time).

So my point is: to the extent TDP accurately measures a CPU's true maximum power dissipation, it's probably a pretty good measure of a CPU's maximum power draw. But OP, keep in mind that the CPU will dissipate a lot less heat than specified by the TDP under "normal usage." Under normal usage, the CPU often has so little work to do that it reduces its clock rate or turns off some of its units (or both).

EDIT: thinking of Intel CPUs here...

 

[cjl]

How much lower?

A lot lower. Most cpus get down to 10W or less at a full idle state.

 

[bonzaiholding]

Thanks for all of your answers.