While unplugged do you have Dell Extended Battery Life enabled? If so try to disable it. Not sure if it is on all systems but I do find that it throttles the system significantly.
Hi, I have a Laptop Dell Inspiron 14 (7400) bought 3 months ago and hardly used. As of today, when I unplug it, the performance slows down incredibly both the browsing and the use of programmes.  I did what was suggested in one of the forums ie. [URL]#M104288 it probably improved by 1% but still  underperforming. Probably some updates conflicting with something else. What can I do to go back to previous performance. Thanks
Laptop slows down when unplugged