Itanium

Itanium (; eye-TAY-nee-əm) is a discontinued family of 64-bit Intel microprocessors that implement the Intel Itanium architecture (formerly called IA-64). The Itanium architecture originated at Hewlett-Packard (HP), and was later jointly developed by HP and Intel. Launching in June 2001, Intel initially marketed the processors for enterprise servers and high-performance computing systems. In the concept phase, engineers said "we could run circles around PowerPC...we could kill the x86". Early predictions were that IA-64 would expand to the lower-end servers, supplanting Xeon, and eventually penetrate into the personal computers, eventually to supplant reduced instruction set computing (RISC) and complex instruction set computing (CISC) architectures for all general-purpose applications. When first released in 2001 after a decade of development, Itanium's performance was disappointing compared to better-established RISC and CISC processors. Emulation to run existing x86 applications and operating systems was particularly poor. Itanium-based systems were produced by HP and its successor Hewlett Packard Enterprise (HPE) as the Integrity Servers line, and by several other manufacturers. In 2008, Itanium was the fourth-most deployed microprocessor architecture for enterprise-class systems, behind x86-64, Power ISA, and SPARC. In February 2017, Intel released the final generation, Kittson, to test customers, and in May began shipping in volume. It was only used in mission-critical servers from HPE. In 2019, Intel announced that new orders for Itanium would be accepted until January 30, 2020, and shipments would cease by July 29, 2021. This took place on schedule. Itanium never sold well outside enterprise servers and high-performance computing systems, and the architecture was ultimately supplanted by competitor AMD's x86-64 (also called AMD64) architecture. x86-64 is a compatible extension to the 32-bit x86 architecture, implemented by, for example, Intel's own Xeon line and AMD's Opteron line. By 2009, most servers were being shipped with x86-64 processors, and they dominate the low...