I've never had a problem with internet in my hotel[s]: these include the Somerset Service Apartment and Hotel [two locations] and Duxton [small 3+ star], plus numerous free internet in the coffee shops.

http://www.nomadicnotes.com/travel-b...nh-city-cafes/

The Starbuck's of Vietnam is: Trung Nguyen Coffee. Go to their flagship shop in D1, near Diamond Plaza and check out their internet service.