How slow is your clock speed in power saver mode?
1st – High performance – 2194
2nd – Power Saver – 1097
3rd – Balanced – 2194
So you can see that the CPU clock speed drops more than 40% in power saver mode on my Dell Precision 6300.

So if you have ever wondered why your computer was so slow when it is unplugged, go check your power settings.
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