2 Replies Latest reply on Sep 14, 2015 3:21 PM by Amy_Intel

# intel core 2 quad Q8300 power equation

HI

I wanted to calculate heating value(Q) cpu Q8300 and I found formula about cpu power dissipation from intel cpu manual.

p=cv^2f

(where, p=power, c=capacitance, v=voltage, f=frequency)

formula is good but I had not capacitace value. (v and f values got from CPUID program.)

Can I get capacitance value from intel official value?

Actually I was calcuate c(capacitance) value already like this c=p/(v^2*f)

p=95w(TDP), f=2.5GHz, v=1.3625 I insert this values at max values so I got (c=20.5*10^-9 F)

this calcuate is correct? I hope so but I think it is incorrect. that's why I am asking you guys!

• ###### 1. Re: intel core 2 quad Q8300 power equation

Let me investigate a little bit further on this and I get back to you as soon as possible.

Regards,

• ###### 2. Re: intel core 2 quad Q8300 power equation

Hellon Jinwon,

Note that processor “capacitance” is not something we specify or something that is constant from part to part.

In general, you can use the equation P=C*V*V*f to determine what the processor’s “dynamic capacitance” (Cdyn) once you’ve measured the power draw.  “Cdyn” is workload dependent so it varies based on processor load. (in the equation, P=Power draw, C= Capacitance, V=VID,f= frequency).

Regards,

Amy.