Dell laptops seem to have brightness issues with Ubuntu. The controls don’t seem to work – although the applet works there is no difference in the screen brightness. To make it worse it is set to maximum brightness and is a drain on your battery power.
There are many posts on this issue but the only fix that seems to work is kamals brightness fix which has been tested for 10.10 and Dell laptops as well.
i915 331519 3 <— an "i915" line should appear
Check to see that the new software sources are enabled
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