Mummelmann on 18 May 2014
I thought this was common knowledge, no? Having low wattage chipsets prevents excessive heat, which in turns saves space and even more power from heat sinks and cooling. It has no bearing on performance (in a positive manner at any rate) but is a good space-saver and possibly saves you money as well (less cooling components).
Contrary to popular belief; it has nothing to do with lowering people's electric bills... 
This is also why chipests shrink all the time in console revisions (and otherswise), smaller chipsets with more transistors per square saves space and cooling output demands and production material requirements, all the while keeping the same relative performance.
