find out current CPU frequency

Tobias Roth roth at
Mon Apr 7 23:49:26 PDT 2003

> > I would like to find out what the current CPU frequency is on my
> > laptop. I strongly suspect that my laptop, as well as many other
> > models, pretty much permanently run on degraded performance, even
> > when under full load.
> >
> > At the moment, I use both 4.8 and 5.0 Release with apm, but I plan
> > to upgrade tocurrent soon.

> dmesg | grep CPU 
> Isn't that good enough? Or do you mean after boot?

no. that is the maximum frequency the cpu runs at, which is fixed. with
intels speedstep there is a possibility that the cpu runs at a lower
frequency than that, depending on the current load.

the idea behind it is this:
high load -> high freq -> high power consumption, more fan activity
low load -> lower freq -> lower power consumption, less fan activity

linprocfs for instance always shows a current cpu freq of 1.1something
GHZ on my 1.8GHz P4. however I have no idea how representative that is.

i strongly suspect that most modern laptops constantly run under a lower
than max frequency, and I would like to know a way to check this.

greets, t.

More information about the freebsd-questions mailing list