[ltp] Thinkpad T61, Ubuntu, cpu scaling

[Yves-Alexis Perez]

On jeu., 2011-06-16 at 10:06 +0100, Alessandro Crismani wrote:
> Hi,
> 
> Could you please elaborate a little more on the issue. Every time I've
> read about battery management it was said to remove it when on AC and to
> store it in a "cold" place (not fridge cold, but not warm either). The
> reasoning behind this, as I was told, is beacuse the main cause of
> battery life loss is heat, which may be high on laptops bottom surfaces.
> Not because of constant charging (which is solved by thresholds as you
> suggested).

Put the battery in the fridge when not in use, yes.
> 
> Whom should I trust?

Henrique :)
> 
> Please don't read this as an offensive mail, I'm not arguing with you, I
> do not know anything about batteries. This is just to ask people (you or
> the list) who have a better understanding of the problem.

The point is: some laptops (especially with discrete GPU and powerful
CPUs) will eat too much power for the adaptor, especially the small
ones. If there's no battery, then in case there's a huge power demand
(cpu+gpu+disk+gb eth+...) the laptop will just shut down because of loss
of power (or maybe not shut down but just do crap silently). So in some
cases (bios detects a 65W adaptor and no battery for example), the bios
(or the EC, I'm not sure) will limit the CPU to only the lowest
frequencies to prevent power loss.

Note that IBM/Lenovo isn't the only one doing that, Dell does the same
afair.

Regards,
-- 
Yves-Alexis