Intel CPUID supplement for P4 was published in July 2000: http://web.archive.org/web/20000815074548/http://developer.intel.com/design/processor/future/manuals/

Intel CPUID supplement for P4 was published in July 2000: http://web.archive.org/web/20000815074548/http://developer.intel.com/design/processor/future/manuals/CPUID_Supplement.htm http://web.archive.org/web/20000815074548/http://developer.i... NT4 SP6 was released in November 1999. Previously, NT4 was truncating CPUID family field to three bits (instead of the correct four bits), as you can see on http://www.geoffchappell.com/studies/windows/km/cpu/identification.htm http://www.geoffchappell.com/studies/windows/km/cpu/identifi... Family 7 was already used by Itanium.