CPU frequency went down

[A. Kromic]

On 07/12/10 22:12, MR ZenWiz wrote:
> On Tue, Dec 7, 2010 at 12:35 PM, A. Kromic <akromic at gmail.com> wrote:
>> This might also be possible, since the fan has failed some months ago
>> and I replaced it. You mean there may be some reason for the CPU to stop
>> working at full speed permanently if it has been overheated? Never heard
>> of that protection mechanism, but if you say it exists, then it could
>> possible... How does that work then?
>>
> It used to be that when a CPU overheated it was dead.  With the advent
> of scaling CPUs, that became less likely since the CPUs would scale
> back their operating frequency to use less electricity and thus
> generate less heat, but I suspect it is still possible that if it's
> overheated long enough it will fail, possibly by not being able to
> scale back up again.  It's a guess - I have no evidence for this.
>
Ok, I investigated the matter a bit further and it seems everything
hardware related we talked about are only coincidences. I've checked the
BIOS first, and it had SpeedStep control on, just as I've left it
before. Then I've tried booting two liveCDs, 10.10 'Maverick' had the
same problem, BUT 10.04LTS 'Lucid'  had the CPU happily scaling up, just
as I had it before. I booted them again to doublecheck, and I confirmed
the behavior. So, it seems my initial suspicions were correct, some bug
has crept in during the Lucid updates, since it started ok when fresh
(and still does so from liveCD). Now I need to identify where the bug
is; I suspect it might be the kernel since it completely fails to scale
the frequency, even when accessed through /proc FS. Are there any other,
perhaps ACPI related components that might interfere with it?

Thanks

-- 
A.Kromic