In the five years before the release of Ryzen, AMD's direct competitor in the x86 and x86-64 consumer-level CPU marketspace, Intel, had continued to grow its market share with the tick-tock improvement cycle of its Core series of microprocessors.[12] Since the release of its Bulldozer microarchitecture in 2011, AMD's CPUs had fallen progressively behind those from Intel in both single- and multi-core performance.[13] Despite a die shrink and several revisions of the Bulldozer architecture, performance and power efficiency failed to catch up with Intel's competing products.[citation needed]