[CentOS] Questions on cpu frequency scaling AMD vs. Intel

Sun Aug 3 14:09:39 UTC 2008
Ned Slider <ned at unixmail.co.uk>

Kai Schaetzl wrote:
> I've been playing and comparing frequency scaling between AMD and Intel 
> CPUs yesterday and there seem to be great differences between AMD and 
> Intel and some gotchas. This is all on CentOS 5.2 with latest Xen kernels 
> (which are supposed to be powersaving-enabled since 5.2).

I was looking at cpu frequency scaling a week or two ago on an Intel 
Q6600 quad core cpu. Rather than repeat myself, there are some numbers 
in this thread (post #6 amongst others):


Bottom line - the power saving between having frequency scaling enabled 
or not was surprisingly small (only 2-3W). It would appear that these 
processors are already fairly efficient at idle and scaling down the 
frequency adds little to the overall savings that may be obtained.