Machine shutting down due to temperature issue

[Nathan Whitehorn]

On 03/31/13 14:35, Julio Merino wrote:
> Hello,
>
> I have a PowerMac G5 (dual PPC 970FX 2Ghz, 6GB of RAM) and recently
> installed FreeBSD powerpc64 9.1-RELEASE on it. Everything is working pretty
> nicely but I keep running into the following issue (which unfortunately
> makes the machine not very usable because I cannot build some software I
> want):
>
> Whenever I try to build pcre, the machine shuts down with this message:
>
> WARNING: Current temperature (U3 HEATSINK: 82.5 C) exceeds critical
> temperature (80.0 C)! Shutting down!
>
> The few information I've been able to find online about the U3 heatsink is
> that it is related to the memory... and the fact that the machine powers
> down reliably during the build of a particularly memory-intensive source
> file in pcre seems to explain this.
>
> Another data point that may be related is that powerd is enabled in rc.conf
> but it fails to start with:
>
> powerd: lookup freq: No such file or directory
>
> Any ideas about what's up with this temperature issue? Is power management
> not implemented for the G5, does it have a problem or is the machine faulty?
>
> I had Linux running on this machine for a while and I didn't experience any
> such issues. Granted, I didn't build pcre, but I used it as a desktop with
> other memory-hungry applications and it behaved nicely.
>
> Thanks!
>

I'd guess a faulty fan on the U3 (which is the northbridge), but it's 
possible there is something else at work. Could you forward the output 
of sysctl dev.fcu?
-Nathan