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I got an interesting problem that I am not sure where to do with. I have a laptop running Debian 6 / Ubuntu 11.10. I have it dual booting. The laptop is a Toshiba m645 s4045.

The problem is something to do with the battery manager in Linux or the power management chip in the laptop.

When I plug in the laptop it charges fine, when I unplug the laptop with a full charge it warns that the battery is critically low and the machine will shutdown soon. Then the battery monitor tells the battery will last 8 hours. Then the battery evens out after a few minutes and reports a lifespan of about 2 hours which seems appropriate for the size of the battery, its a 6 cell battery.

What the heck is going on with my laptop? I thought it was the battery (the original one) so I bought another battery, this did not solve the problem.

Could it be Linux acting up? Could it be hardware?


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up vote 1 down vote accepted

It sounds like you need to condition the battery. Charge it fully. Then, set the laptop to always run on full power. Next, unplug the power, and let the battery run down to flat, and let the machine power off. That should reset the power management hardware, and it will do a better job of estimating the battery life. You may need to do this once or twice with each battery.

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i tried that with the first battery, no dice. Could it be the power management hardware? like the circuit on the motherboard? i am wondering because this laptop is not mine and i might not buy it if that could be an issue. – ianc1215 Oct 24 '11 at 5:29
Did it run for about the 2 hours that the battery monitor said it would? If so, then I'd call it "one of those things" and not worry too much. If not, then I'd suspect more of a problem. If it's a machine you might buy, and you don't know how long it ran for, do the test again and make sure that the battery life is about what the monitor said it would be. Then make a decision based on that. – mauvedeity Oct 26 '11 at 7:04
Well to be honest I did not really keep track of the amount of time the machine ran for. It probably "about" an hour or so. So no I am not getting the battery life I should. Thanks for the help. – ianc1215 Oct 27 '11 at 7:29

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