When in doubt use the supplied cable and charger together. 99% of the time this will work.
The issue is this tablet needs a 2 amp power source AND a charge only cable (charge only cables have the data pins shorted). Some cables dont work no matter what. For example: the cable that came with my Chromecast will not work not matter what charger I am using.
The stock Dell cable will work with the stock charger, my samsung charger, my google nexus 7 charger and my battery pack. The stock cable will not charge when plugged in to a Pc, or USB hub or an older charging device.
I have noticed my Samsung cable will work with my Nexus7 charger, but will not work with my other 2amp wall chargers. Lots of reports that Nexus7 charger is smart enough to short the right pins as needed.