Amd Athlon 64 4000+ Processor Socket 939 939 Pin architecture Get powerful performance for your unique digital experience.The AMD Athlon 64 processor is the first Windows-compatible 64-bit PC processor. Built-in support for future 64-bit applications with AMD64 technology Guard your data with AMD Enhanced Virus Protection for Microsoft Windows XP SP2 HyperTransport technology and an integrated DDR memory controller for maximum performance and system efficiency.