amd64/102148: The description of which Intel chips have EM64T is out of date

Mike Meyer mwm at
Wed Aug 16 14:20:16 UTC 2006

>Number:         102148
>Category:       amd64
>Synopsis:       The description of which Intel chips have EM64T is out of date
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    freebsd-amd64
>State:          open
>Class:          doc-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Aug 16 14:20:14 GMT 2006
>Originator:     Mike Meyer
>Release:        FreeBSD 6.1-PRERELEASE amd64
Meyer Consulting
	All amd64 ports.

	The HARDWARE.TXT file on the 6.1 RELEASE cd uses out of date
	text to describe which Intel processors support EM64T. It ignores
	newer processors with EM64T support, and is factually wrong, as some
	of those chips have model numbers that the text claims don't have
	EM64T support.

	for more current information. Note in particular that the
	freebsd page says that 5xx processors do not support EM64T,
	but the Intel page says that the 521, 551, 561, 571 (but not
	the 511) do have that support.

	Suggested new text:
	All Intel Core 2 (not Core Duo) and later processors will have
	EM64T support. All Pentium D processors have EM64T support.
	All multi-core Xeons except Sossaman have EM64T support. The
	single-core Xeons with EM64T support are Nocona, Irwindale,
	Potomac and Cranford.  Pentium 4s and Celeron Ds using the
	Cedar Mill core have EM64T support. Pentium 4s and Celeron Ds
	with the Prescott core all have EM64T support in the core, but
	it is not enabled in all of them. There is no easy way to
	describe which Prescotts have EM64T enabled; see Intel's docs at
	for details. 


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