[kennedy]

Does anyone know if Windows XP has implemented high processor temp shutdown logic?

Does anyone know if Parallels would pass through the Intel overheating signals to Windows?


Why do I ask?

Because my machine is experiencing BOTH random shutdowns of the Mac side AND consistent shutdowns of the Windows XP side (running inside Parallels). I've tried all forms of virus removal... it doesn't appear to be a virus.

The current think on the MacBook Random Shutdowns is that it's due to a faulty heat detection circuit in the MacBook. Looking at the Intel Duo Core info, there are a couple levels of overheat signals... one intended to be used by the machine or OS to gracefully shutdown the machine... the other causing an immediate power-off.

I am thus guessing that the "graceful overheat" signal is now always on and the "immediate overheat" signal is coming on randomly. So, the Mac side, which ignores the graceful signal turns off randomly. And the PC side, which handles the "graceful overheat" signal is shutting down in roughly 60-90 seconds.

Thoughts on that theory?

[ghporter]

That should be a function of the hardware, not the OS. I've seen a number of different computers with sensors for the CPU's temperature (and sometimes for other chips as well), and those sensors, though available to the OS, are USED by the logic/motherboard to protect the chip.

Think of it in these terms: if there's a problem with heat dissipation (no heatsink, for instance) then the CPU would get very hot very fast-before the OS would have a chance to load. How would an OS-based temperature protection system help in this case? On the other hand, something on the board that says "CPU is too hot! Shut down!" would certainly do the job. And since you experience shutdowns under both OS X and Windows, (which do a lot of things very differently internally as well as externally) that should also reinforce that it's a hardware feature, not something the OS handles.

I pretty much agree that it's quite possible the MB random shutdown issue has something to do with thermal regulation, but it's not something related to whatever OS you may be running at any particular time.

[kennedy]

Originally Posted by ghporter

Think of it in these terms: if there's a problem with heat dissipation (no heatsink, for instance) then the CPU would get very hot very fast-before the OS would have a chance to load. How would an OS-based temperature protection system help in this case?

The OS can shutdown gracefully... like NOT in the middle of saving a file such that the file gets trashed.

On the other hand, something on the board that says "CPU is too hot! Shut down!" would certainly do the job.

Well, it'll get the CPU off... but it may trash some files in the process. Not so graceful.

And since you experience shutdowns under both OS X and Windows, (which do a lot of things very differently internally as well as externally) that should also reinforce that it's a hardware feature, not something the OS handles.

Actually, just the opposite. In this case, Windows XP is shutting down in a big hurry... but the Mac is NOT shutting down at the same time. Just Windows quits inside Parallels... the Mac keeps running. For a while... later, the Mac turns off too.

Soooo, that says either Windows XP is handling the earlier temperature problem in software... OR Windows is shutting down for some other reason that is just a coincidence.

[ghporter]

Gracefully shutting down may not save the CPU-all the hardware shutdowns I've seen have been exceptionally sudden. Just BOOP! and it's off. In fact on one computer I built it only came on long enough to turn on the CPU fan before it shut itself off. (Following the manufacturer's instructions on connecting the heat sink to the CPU turned out to be the culprit-their "thermal pad" was poo, so I used decent generic heatsink compound and all was well.) And with saving the hardware being the purpose, graceful, file system saving shutdowns are a secondary concern.

Now to the real meat! I had not gathered the item of Windows shutting down within Parallels but not shutting down the Mac. Different animal alltogether. When you say it's "shutting down in a big hurry" does that mean that it just quits and dumps you to some Parallels screen? Do you get any sort of message or the "Windows is shutting down" screen?

I do not think Windows XP actually deals with shutting down for thermal events - but I'll check on that because I don't KNOW that's true. I've never found a reference to say that it does...

[kennedy]

No, no message... it just shuts down and returns to the normal Parallels window with configuration settings. Much like the Mac Random Shutdowns... but not so random... reliably within 60-90 seconds.

[ghporter]

Ok, that's just plain weird. I've never seen Windows "just shut down" without some sort of message-and even a BSD/memory dump is some information. Of course I don't have any experience with Parallels, so I don't know if it just eats such output or passes it on...

I'm officially saying "I'm lost here" so anyone with a clue is welcome to chime in any time!