There are three options total for you to consider.  The vast majority of our 980's will use the ACX 2.0 cooler which is relatively quiet on 100% when compared to the single fan design at the same speed.  The last option would be water cooling via the Hydrocopper edition.  
 
Overall you can use more fans with a water cooling set up but have them run them at much lower speeds for equal if not better thermal performance with very little noise but there is a cost associated with getting a water loop established in the system which may or may not be something you would deem justifiable.
 
There are also certain PC cases that take steps to reduce noise by using sound dampening materials on the panels but do also insulate the system, possibly raising the ambient temperature in said system.