I am experiencing problem with versions from 10 to 13 of Ubuntu on Dell Latitude E5420, specifically. The behavior is very weird. If Ubuntu is started without power supply plugged in, the notebook works as a charm. At the moment the charger is plugged in, the notebook starts working slowly, the mouse pointer is moving like an ant. Unplugging the charger turns Ubuntu back to its normal condition. Plugging it in, back, repeats the issue. If Ubuntu starts with power supply plugged in and 100% charged battery it is OK, however if not with fully charged battery and on power supply, the issue occurs again. So far, I believe this happens only on that model of Dell. On Latitude E5410 I did not manage reproducing it. Has anyone of you had such a case?
I had this problem on UBUNTU 13.04 on the same laptop (Dell latitude 5430)
I did a simple thing - just a lucky shot - .. updated all the xserver packages that I had as follows:
it will correct you and show about 3 xserver packages .... install them all (they should be installed .. but whatever)
then upgrade them
and it is solved now ^_^