Problem on AMD64

[David van Kuijk]

>>>>
>>>> Thanks for the responses so far.
>>>>
>>>> I would be happy with S3. I am however a little confused about the
>>>> abilities of  my server as reported by sysctl hw.acpi.
>>>>
>>>> As commented below this line suggests that no other states than S4/S5
>>>> are supported:
>>>> hw.acpi.supported_sleep_state: S4 S5
>>>>
>>>> But this is also listed:
>>>> hw.acpi.standby_state: S1
>>>> hw.acpi.suspend_state: S3
>>>>
>>>> Are these last two overridden by the first, meaning that S3 is not
>>>> available from my BIOS???
>>> Yes. FreeBSD, by default, sets up standby as S1 and suspend to S3 because
>>> almost all BIOSes support these states. Yours is the first BIOS I have
>>> seen that does not do S1. That is really odd.
>>>
>>> In any case, you have no available ways to cut power when your system is
>>> really idle other than powering off. Of course, you may be able to do
>>> some power saving with powerd and EST if your BIOS and CPU support those.
> 
> Look into the following sysctls:
> 
> hw.acpi.cpu.cx_lowest
> hw.acpi.cpu.cx_highest
> 

I tried to find out what I can do with those sysctls.
hw.acpi.cpu.cx_highest is not available on my system.
hw.acpi.cpu.cx_lowest is available and can be set. Are you suggesting I 
should set it to C2 or C3???

A second question;
When I use powerd it switches between clock-frequencies of 1800 and 1000 
correctly. Is it possible to set a sysctl so that even lower frequencies 
are supported, or are the supported frequencies simply dictated by the 
processors in my server (in my case Opteron 1.8 GHz)?

Cheers,
David