The story I heard (which I can't corroborate) was that it was Microsoft that nixed Intel's alternative 64-bit x86 ISA, instead telling it to implement AMD's version instead.

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smashed 7 hours ago | parent | next [-]

Microsoft did port some versions of Windows to Itanium, so they did not reject it at first.

With poor market demand and AMD's success with amd64, Microsoft did not support itanium in vista and later desktop versions which signaled the end of Intel's Itanium.

	▲	wmf 4 hours ago \| parent \| next [-]
		Microsoft supported IA-64 (Itanium) and AMD64 but they refused to also support Yamhill. They didn't want to support three different ISAs.
	▲	6 hours ago \| parent \| prev \| next [-]
		[deleted]
	▲	Analemma_ 7 hours ago \| parent \| prev [-]
		Microsoft also ships/shipped a commercial compiler with tons of users, and so they were probably in a position to realize early that the hypothetical "sufficiently smart compiler" which Itanium needed to reach its potential wasn't actually possible.

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antod 3 hours ago | parent | prev [-]

Yeah, I remember hearing that at the time too. When MS chose to support AMD64, they made it clear it was the only 64bit x86 ISA they were going to support, even though it was an open secret Intel was sitting on one but not wanting to announce it.