I just did a clean reinstall of Ubuntu (10.04 --> 10.10). After the install, any time I do CPU intensive work, my PC is suddenly shutting down like it's overheating.

Everything was working fine for months, and started having problems immediately after the reinstall. so this is not a problem with my hardware, and it's not a problem with my fans needing cleaning -- it's a problem with software. So please don't tell me "that sounds like overheating, clean your fans". Something is different in software-land between 10.04 and 10.10 that is causing this to happen -- I assure you that the upgrade did not magically fill my fans with cat hair.

I have checked my log files, and can't find anything related to overheating -- searches for things related to lm_sensors, "temp", and "thermal" are not turning up anything in the system logs (syslog, kern.log, or messages). I also looked at the logs around the times of the sudden shutdown, and couldn't find anything unusual.

How can I diagnose this? I'd like to file a bug report, but since I can't find anything in the logs, I honestly have no idea how to go about providing useful information.

Is there anything besides overheating that might be causing my laptop to suddenly shut off?

Thanks,
Jesse

(I am using a Gateway M-6888u laptop, btw)

I giggled around a bit and the power supply seems to be the next candidate on the most likely list. Here's a good rundown on checking out the power supply.

This site indicates that some video cards have their own fan and can cause this.

You might run GkrellM or some other status monitor and turn on the temperature sensor. If your computer has a temp sensor (and I think that most newer laptops do), that would enable you to eyeball the temperature as you work.

GkrellM is in the Ubuntu repos.

I don't think this is a problem with the power supply. I think this is a software problem.

Everything worked fine for months before the upgrade. Everything worked this morning before the upgrade. Immediately after the upgrade, my power supply suddenly failed? Highly unlikely ...

The temperature is definitely high -- 82 C ... so now it's just figuring out why it's not getting cooled off properly. Any suggestions?

Sounds like the ACPI module doesn't like your computer. Try disabling ACPI and APM on the motherboard. If it fixes the problem then you know the cause.

Of course it's a software problem. However if it is ACPI then you can either live with that disabled on the motherboard or disabled in the operating system.

The simplest option may just be to revert to 10.04.

I'm not sure why, and don't have time or desire to figure it out, but for whatever reason downloading the ATI FGLRX proprietary drivers seems to have made it stop crashing ... thanks for all of the help though.

Thanks for the update.

A new problem solving technique. Sounds like fun.