>Intel's project was originally codenamed Yamhill. After several years of denying its existence, Intel announced at the February 2004 IDF that the project was indeed underway.
If Intel wasn't so focused on the Itanium they would of beat AMD by years.
Anybody who was following the industry at the time knew about Yamhill at least by 2002, though Intel had conceptions on how to extend x32 to x64 well before that in a natural way, but instead went the resource and engineering draining Itanium route, allowing AMD to produce the first available chips.
While I only know murmuring on the peripherial about Intel's early x64, I'd love to hear insider knowledge about why management decided Itanium was so hot that they dropped everything about bringing x32 to its logical x64 conclusion.
* they would have beaten
Isn’t that exactly what the title says? Which bit are you quibbling with? Or has the title been changed?
In that case just call it x86 as a catchall. But if you're going through the effort to specify the 64 bit ISA, then "Intel's" stops being particularly correct.
AMD pioneered this version of the instruction set with AMD64, and Intel actually adopted it as Intel 64, with minor differences[0].
[0] https://en.wikipedia.org/wiki/X86-64#Intel_64