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FunkyRes

macrumors newbie
Original poster
Aug 26, 2003
6
0
Here's the story.
I live in Redding, CA - and sometimes it gets very very very very hot.

I do not have air conditioning.

I have a bondi iMac running Linux acting as a cvs server.

What I want to do is write a cron script to check the cpu temperature ( I can get that from /proc/cpuinfo) and shut the mac down if it is getting too warm.

The problem is - I have no clue what the temperatute range of these things should be.

How hot do y'all think is too hot?
 
It think too hot is at 111 degrees on those machines, My G3 minitower that I overclocked crashed when it reached about 115 degrees with two fans. but since teh imac has has a much smaller fan i would say about 110-112 or so...
 
all iMacs have a failsafe already built in. if they get too hot, they will shut down on their own. You don't need to do anything. If you are wondering where this information came from, it came from the moderators on apple's discussion forums.
 
I don't believe that applies to the the original tray loading iMacs.

I think that's only true with the fanless slot loaders.

Even if it is true, I have no way to test that the mechanism actually works. I can test a script that shuts her down at certain temp is reached.
 
well I dont think the imac's chip has a built in temp sensor that is accessable through anything but the built in heat failsafe that was mentioned before.
 
Built in fail safe or not - Can anyone answer my original question?

It probably would be better to shut down this thing before it gets to the point of built in failsafe anyway.

It's much better for the filesystem (I'm running linux) if the mac goes down clean opposed to abruptly powering off.

Even with journaling filesystem - it's still always better to shut down a computer through the OS than to just have it power off.
 
Originally posted by applemacdude
I would have to say that you should shut it off at about 105-110 degrees. What is the temp of your imac now?

Right now its 45 centigrade.
The outside temperature is 34 centigrade and the temperature in my kitchen is 32 centigrade.

The outside temperature in Redding sometimes goes above 45 centigrade - and w/o air conditioning, it gets pretty close to that indoors.
 
OK - from the graph, I think 48 centigrade is where I'm going to make my cutoff for this mac.

#!/bin/bash

---
TEMP=`grep "^temperature" /proc/cpuinfo \
|cut -d ":" -f2 |cut -d"-" -f2 |cut -d " " -f1`

if [ $TEMP -gt 47 ]; then
echo "Temperature Shutdown at `date`" >> ~/temperature_shutdown
/sbin/shutdown -h now
fi

exit 0
---

I'll run that from root's crontab every minute.
That should do the trick.

Thanks.
 
I had to bump it up a little bit.
In the morning, when it is cool, the cpu exceeds that temperature when just compiling software (and the cools back down real quick)

I'm not going to be compiling a lot of software on it (I was just compiling a newer version of CVS) - but still, I clearly had the automagic shutdown set too low.

I bumped it up to 54 centigrade.
 
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