Laptop suddenly shutting down?

[x C0MMAND0 x]

This isn't really an Ubuntu question, more of a general laptop/hardware question, but these forums have lot's of smart brains so I thought I'd try and see if anyone can help.

My laptop (Dell XPS M1330) will suddenly shut down...completely and instantly turn off when it's not plugged in. Sometimes this happens after 5 minutes of being unplugged, sometimes it's an hour after being unplugged. The physical power light on the battery lights up almost all of the way, and my system (both in Kubuntu AND Windows 7) will show the laptop battery as being almost fully charged and say "2 hours" or so remaining.

Any ideas of what could cause it to suddenly power off? Any ideas of a way I can test anything or check any logs? I don't know if it's a battery problem, or a problem with something else on the laptop, but I'm pretty sure it's not an OS issue.

Any thoughts?

[2F4U]

Could be an issue with overheating. Did you look into the system log files, since these may contain additional information on why it suddenly shut down.

[x C0MMAND0 x]

It doesn't do it when it's plugged in though, and I monitor the temperature constantly and it very rarely exceeds 50C for the CPU and around 65C for the GPU which is pretty cool.

[x C0MMAND0 x]

Any other ideas?

[Mark Phelps]

Maybe Dell readings are more useful, but I found the battery readings in Ubuntu for Toshiba, HP, and Fujitsu laptops, in terms of useful time remaining -- to be all but useless.

So, if you're using that to judge the remaining useful time on the battery, you could be seeing bad information.