Re: High pitch noise when ACPI processor module is loaded.

[Robert Hancock]

On 01/23/2010 02:12 PM, Rafael J. Wysocki wrote:
> Messages about ACPI should be CCed to linux-acpi@xxxxxxxxxxxxxxx (added).
>
> On Saturday 23 January 2010, Justin Piszcz wrote:
> > Hi,
> >
> > Linux:
> > When I do not load the ACPI processor module, there is no high pitch
> > noise.  When I load the ACPI processor module (so I can utilize Turbo
> > Boost), Linux makes the system emit a high pitch noise.
> >
> > Windows:
> > The same system, running Windows 7 does not emit any noise.
> >
> > Is there something wrong with the ACPI processor module or its
> > implementation on i5/i7 CPUs?

May not be anything "wrong", but some systems do have an issue with the 
voltage regulator circuitry where it can make noise with certain 
combinations of power draw and wakeup rates (causing rapid current draw 
fluctuations) where some of the components can resonate and make noise.

What does powertop report for this system? It might show some useful info.
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