IBook randomly turns off *when plugged in,* how long can my iBook last me?

Question

O Sages of Mac Wisdom,
Help! I've been Googling and looking at forums all over the place for help. I have seen many posts about other iBooks shutting off randomly when they are on battery power, but have not seen any that answered questions about iBooks turning off when they are plugged in. It happened four times in the span of two and a half weeks and has stopped (no incidents for the past two weeks). I have reset my PRAM and PMU. Why would it be turning off on its own when it is plugged in?
Second question: my battery only lasts for about a 45 minutes from a 99% charge. Here's the information on it:
Battery Information:
Charge Information:
Charge remaining (mAh): 1438
Charging: Yes
Full charge capacity (mAh): 1544
Health Information:
Cycle count: 95
Battery Installed: Yes
Amperage (mA): 934
Voltage (mV): 12508
I bought a new battery from ifixit.com, rated at "good" condition, and it will last for an hour until it gets to 75%, then drops down to 0% in five minutes and the iBook goes to sleep. It could be just that they gave me a crappy one, but here's the information on it anyway:
Battery Information:
Charge Information:
Charge remaining (mAh): 5236
Charging: Yes
Full charge capacity (mAh): 5804
Health Information:
Cycle count: 91
Battery Installed: Yes
Amperage (mA): 962
Voltage (mV): 12511
Thoughts?
Final question: I have some extra money now, and I won't after July, when I'm done with my MA and have to break down and find an actual job (also won't have the Ed Discount after July). I want to get the most out of this iBook, but I also don't want to be screwed in a year or two and not be able to afford a new computer. In other words, do you have any estimate on how much more mileage I can get out of this one? Any past experiences anyone has had would be helpful!

Answer 1

Hey steck and Welcome to Apple Discussions,
Why would it be turning off on its own when it is plugged in?
Have you been on the machine when this happens? Are there any unusual symptoms when this happens?
Next:
Download Temp Monitor here and run it:
http://www.bresink.de/osx/TemperatureMonitor.html
report back
There could also be a DC in board problem or a PMU problem.
Battery problem:
Charge Information:
Charge remaining (mAh): 1438
Charging: Yes
Full charge capacity (mAh): 1544
That's about a third of what it should be.
The ifixit battery:
Charge remaining (mAh): 5236
Charging: Yes
Full charge capacity (mAh): 5804
That one should run it for 5 hours. It could be bad.
Did you calibrate it when you got it?
http://support.apple.com/kb/HT1490
In other words, do you have any estimate on how much more mileage I can get out of this one? Any past experiences anyone has had would be helpful!
Well with your current situation, there is a big question mark. However I use and continue to use a 14" 1.2 iBook and feel very confident in it. Mostly I know the problems that can occur and have repaired all of them myself. I also repair and donate them to inner city school teachers, since I can get good deals on broken ones (or they're donated).
Sort of like this:
http://www.lowendmac.com/ed/herlihy/09ph/ibook-netbook.html
Richard
Message was edited by: spudnuty
Message was edited by: spudnuty