Problems with Core i3 notebook

[Liam Proven]

I am currently using a Core i3-powered MSI CR620 notebook. It's good
for a budget machine.

This is a related model:
http://uk.msi.com/product/nb/CR620.html

But on Ubuntu 10.04LTS, 11.04 and 11.10 it exhibits the same problem.
If I unplug it from the mains, although the battery meter says there
is 2h50m of power remaining, the screen goes dim and it immediately
says that the battery is critically low and it is about to shut down.

Any suggestions as to where to start investigating this?

-- 
Liam Proven • Info & profile: http://www.google.com/profiles/lproven
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