ACPI on Compaq Presario 702EA Laptop

[Wilhem Meignan]

Hi everyone,

I have FreeBSD 5.1 RELEASE on my laptop and I have some questions regarding ACPI.

It seems that by default, the CPU (AMD Duron) is always running at maximum speed.  Also, I think that normally a thermal zone has to be detected and its parameters accessible through sysctl, right?
This is not the case on my laptop.  I don't have any information concerning thermal zones accessible through sysctl.  I have read somewhere that with ACPI the OS is responsible for turning on and off the active cooling devices.  What does FreeBSD does when no thermal zone is detected?  The behaviour I have observed is that, at first, the fan is turned off then, when the computer has warmed up it is turned on and doesn't seems to stop anymore.

So, I get a laptop that run quite hot with the fan always on.  I would prefer that the fan would be turned on only when needed and with CPU throttling the speed of the processor should be slowed down when the computer doesn't have much to do to reduce power consumption and heat production.

What is the status of FreeBSD concerning those points?  Is there anything I can do to have those features and/or a thermal zone correctly detected?

Thank you very much in advance,
Wilhem.