Re: 2 core dumps

On Fri, 2008-02-22 at 12:09 +0100, Dag-Erling Smørgrav wrote:
> Mikael Ikivesi <mikael.ikivesi_at_pp.inet.fi> writes:
> > I have checked for overheating as it was my first quess but the answer
> > is no. And these dumps happened without powerd. I only manually enable
> > 1800Mhz sometimes if I need extra speed. It seems to be highest
> > sustainable speed for this machine. Powerd heats this laptop too much
> > without manually setting _PSV value to much lower. And the result would
> > be the same 1800Mhz.
> 
> Your laptop overheats when running at its rated frequency?  That's your
> answer.  Hardware error.  Most likely incorrect application of heat
> transfer compound between the CPU and the heatsink, or blocked or
> defective fans.  If your CPU has overheated even once, you can't trust
> it any more, unless it has an automatic cutoff like Core and Core 2.

If "overheated" in this context means "initiated critical shutdown"
neither statement needs to be true. For instance, there is the patch
from Umemoto-san floating around acpi_at_ that enables use of passive
cooling for the thermal zones other that tz0, and there is at least one
model of laptop that I know of, which uses tz1 for its CPU. This means
that FreeBSD *will not* handle passive cooling on such laptop and it
might reach _CRT and shut itself down. Also, some manufacturers put _PSV
dangerously close to _CRT, assuming that OS will take over in time,
which might or might not happen in the real life.

However, if "overheated" means "discolored and deformed plastic parts",
you are absolutely right.
> 
> DES
-- 
Alexandre "Sunny" Kovalenko (Олександр Коваленко)