The Intel QuickPath Interconnect (QuickPath, QPI) is a point-to-point processor interconnect developed by Intel which replaces the front-side bus (FSB) in Xeon, Itanium, and certain desktop platforms. It was designed to compete with HyperTransport. Intel first delivered it in November 2008 on the Intel Core i7-9xx desktop processors and X58 chipset. Intel developed QPI at its Massachusetts Microprocessor Design Center (MMDC) by members of what had been DEC's Alpha Development Group, which Intel had acquired from Compaq and HP. Prior to the name's announcement, Intel referred to it as Common System Interface (CSI). Earlier incarnations were known as YAP (Yet Another Protocol) and YAP+.
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