According to the Dell'Oro Group, starting in 2015, cloud data centers will emerge as the sole growth driver for server shipments, as unit shipments into enterprise data centers decline. Server unit shipments are expected to continue to grow overall during the forecast period.

"Our recent interviews with end-users, component vendors and system integrators, indicate that cloud adoption is occurring faster than industry expectations," wrote Sameh Boujelbene, director at Dell'Oro Group. "The substantial increase in cloud uptake stems from both a declining skepticism of the cloud among enterprise accounts, and the willingness of cloud vendors to hear their customers' concerns, mainly related to security and resiliency, and to provide platforms to meet their needs. We currently expect cloud servers to reach 50% of total server shipments by 2017, a year earlier than previously projected."

Dell'Oro says servers' migration to the cloud holds significant implications for server form factor, even challenging the basic definition of a server.