[LAU] thinkpad t61 noise

[Dominic Sacré]

On Fri, Oct 1, 2010 at 12:23 PM, rosea grammostola
<rosea.grammostola at gmail.com> wrote:
> My thinkpad t61 makes a high frequency sound, pipipipipippi, not very
> loud. Funny thing, when I stick in the usb mouse, it's gone... I only
> have this issue when on battery. Suggestions for solution?

Many Thinkpads (and other laptops as well) emit high-pitched noise
when the CPU periodically goes into power save mode. As far as I know
there is no real solution. You can change some kernel or BIOS settings
to (partially) disable power saving, but that might reduce your
battery life quite significantly.

I once had a similar problem which could also be "solved" by plugging
in USB devices. Turns out there was a bug in the USB kernel driver
which caused continuous CPU wake-ups, and thus prevented the CPU from
going into deep sleep modes. This stopped the noise, but also
increased power consumtion by a couple of watts...

Incidentally, another way to keep the CPU awake is to simply run JACK :)

This page has a lot more information and many potential workarounds:
http://www.thinkwiki.org/wiki/Problem_with_high_pitch_noises


Dominic