Mark wrote:
> Hi
>
> I recently received my new Dell 640m with Core 2 Duo processor -
> lovely! Except I got an annoying high pitch noise - barely detectable,
> but annoying people with good hearing!
>
> So, looking on the forums, it seems people are reporting the same
> problem on various machines, and it seems to be related to the CPU and
> the frequency it runs at setting up some sort of resonance.
>
> The advice was to download RM CPU Clock utility (freeware, and very
> good!) and disable the "Enable Popup Mode" tickbox in the "Advanced CPU
> Settings" section.
>
> http://forum.tabletpcreview.com/showthread.php?t=3516
>
> I have tried this, and it really works! I can clearly detect the noise
> stopping/starting as I toggle this setting.
>
> I cannot immediately detect and down sides to this change of setting -
> the RM Clock readme states:
>
> "Enable Popup mode (auto C3/C4 to C2) - when this option is off, any
> bus master traffic causes the chipset to return from C3 or C4 state
> into C0 (working) state. When this option is on and the chipset
> observes a bus master request, it will take the system from C3 or C4
> state into C2 state and enable bus masters. This will let snoops and
> memory access occur. This setting is available only for ICH6-M and
> ICH7-M."
>
> I would really appreciate if anyone translate this into real-world
> performance/heat/battery life information for me :)
>
> Hope this helps people,
> Mark.

Hi - further tests indicate that the CPU core temperature idles at
40degrees with Popup mode enabled, but goes up to 44degrees with it
disabled.

Hmm, this annoying: either take the whine, or a hotter CPU (which
presumably means less battery life, and more fan noise!)

So, if anyone else has some ideas, I would appreciate them!

Mark.