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Why does my computer get less battery life with Ubuntu compared to Windows?
When I used Windows 7 with Dell Inspiron, I got a battery life of 2 hours. But ever since I installed Ubuntu, the battery life has taken a hit. When I recharge the battery to almost full and then unplug it from power socket, the battery shows 1:42 hours. But within a minute, this drops down to 0:41.
I even installed powertop 1.97 to combat this, but only configurations I can do in powertop is within tunables, which is shown in the figure.
I heard that powertop almost increases battery capacity by double. So, what should I do?