Desktop power consumption.

[CuriousMike]

I can run my mobile XP reliably at 11*200 = 2200mhz at 1.55v, or reliably 12*200 = 2400mhz at 1.8v.

The difference in CPU temperature is pretty big.. 10' C.

Is there a way to tell the overall power consumption added to the processor for the .25v increase ?

i.e., running @1.55v = the processor eating 60w, where running @1.8v = 80w.

 

[Bobthelost]

There is, but i haven't got a clue what it is 😀

The difference in power consupmtion is tiny in monetary terms.

 

[Matthias99]

Originally posted by: Bobthelost
There is, but i haven't got a clue what it is 😀

The difference in power consupmtion is tiny in monetary terms.

It's roughly a linear increase in power consumption for increasing clockspeed, and a quadratic increase for upping voltage. So a 10% increase in clockspeed will require about 10% more power, but a 10% increase in voltage will require (1.1^2 = 21%) more power. However, there's no simple formula that says "chip A, at clockspeed B and voltage C, will use X watts."

Going from 2200Mhz@1.55V to 2400Mhz@1.8V should increase your power draw/heat by about (2400/2200) * (1.8/1.55)^2 = 1.091 * 1.471 = 1.604 -- roughly 60% more heat/power! How much of a temperature increase it causes depends on the cooling you have.

A64s generally use somewhere from 50-90W under load at stock (depending on speed and cache size). You might be able to look up some numbers on your particular model if you search around.

 

[CuriousMike]

matthias -- thanks for the info -- it seems like it's something I can work with.

That does seem incredible that an additional .25v increased overall power consumption 1.6x.

 

[JimPhelpsMI]

Hi, Mathias has it right! Simply put: More voltage causes more current. Volts (E) times Current (I) = Wattage and wattage = heat. Jim