I have a Dell Venue Pro 11 7140 BLK which has an Intel Core M 5Y10a processor which experienced a battery charging problem a few days after purchase at Best Buy. The battery level continued to deplete even when connected to the ac adapter. The Dell Support agent remotely installed Dell Fixit software which let him re-flash a chip which fixed the problem. Afterwards he removed the Fixit software. The Dell Support agent said that this battery charging problem could sometimes occur if the 2-in-1 tablet was connected to the ac adapter for too long. He recommended connecting to the ac adapter for no longer than 4 hours.