Power problem is not likely. Hard drives can get buggered up in shipment, rendering them defective. Seagate is very good about replacement. The clicks are indicative of excessive impact.
I second the suggestion to use the Sea Tools... the software on the Seagate site can diagnose the reasons for most hard drive failure and performance issues. Once you have that info, dealing with Seagate is easy and relatively quick.
However, Seagate can also tell if the drive experienced excessive impact from the side while running. That sort of damage is not covered under warranty.