I'm new to Arch (fairly experience with Linux in general but wouldn't consider myself an expert) I have recently installed it on an HP/Compaq nw8440 laptop. I am having problems with the machine powering down. Not just suddenly shutting off like I pulled the battery but randomly acting like I typed "shutdown -h now" as root. I first saw this issue when trying to install Cinnarch and reinstalled Windows XP and ran the machine through a burn in (assuming overheating) with no problems. I thought maybe it was an issue with Cinnarch and installed Arch proper, The machine ran for hours from the command line with no issues but shortly after starting X11 (with TWM) it shutdown. I have since noticed it shutdown when at the command line (but it seems to happen a lot more quickly when X11 is running) I installed the lm-sensors package and configured it. The output of the sensors command gives me
adapter: isa adapter
as well as the current temperatures and the "Crit level temperatures" for each sensor. The only sensor that looks like it might be showing abnormal temperatures is acpitz-virtual-0 temp 3, it starts around high 70's/low 80's, and creeps up. I have seen it hit 109C (Crit temp is labeled as 110C) several times now right before the laptop shuts down. I can only assume at this point that the machine is shutting off trying to protect itself from overheating, but every other sensor is showing great temperatures the only fan that I can determine if it's running without pulling the laptop apart is running fine, and I have no clue what acpitz-virtual-0 temp 3 is monitoring. Can anyone point me in the right direction, I haven't had much luck so far trying to figure out what this temperature is being measured for, why it's overheating or how to fix it. I have looked through some logs and have seen nothing that would give me a hint as to the problem (although having never really dealth with the system logs on a Linux machine before perhaps I wasn't looking in the proper place).
My previous laptop was an MSI laptop that would shutdown like that when I accidentally unplugged the power cord and didn't realize it. When the battery ran down, it would erroneously report critical temperature rather than low battery, and perform a shutdown.
Is it possible your power cord socket is coming loose, and the battery is low?
I know it is unlikely, but that describes the problem I had pretty closely.
So I kept searching around and found something in an Ubuntu forum about a similar problem with the fglrx drivers and the performance modes. His was set to high by default and would overheat. I installed a utility to check this out and my card was set to high performance, I changed it to low and the Temp 3 that was causing me problems immediatly started dropping and averages about 80C and the laptop is perfectly stable. While there is still more to figure out, why is it overheating when it wouldn't in Windows (perhaps the driver isn't running the fan correctly), how do I set it to default to low instead of high etc, since I'm not really going to be using this machine for games this is a workable solution for the time being. For now I have a better idea of where to start looking and am considering this thread closed.