From owner-freebsd-questions@FreeBSD.ORG Thu Nov 17 20:04:38 2005 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 59BC416A41F for ; Thu, 17 Nov 2005 20:04:38 +0000 (GMT) (envelope-from cswiger@mac.com) Received: from pi.codefab.com (pi.codefab.com [199.103.21.227]) by mx1.FreeBSD.org (Postfix) with ESMTP id BF82343D49 for ; Thu, 17 Nov 2005 20:04:37 +0000 (GMT) (envelope-from cswiger@mac.com) Received: from localhost (localhost [127.0.0.1]) by pi.codefab.com (Postfix) with ESMTP id 282985F7E; Thu, 17 Nov 2005 15:04:37 -0500 (EST) Received: from pi.codefab.com ([127.0.0.1]) by localhost (pi.codefab.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 06480-04; Thu, 17 Nov 2005 15:04:36 -0500 (EST) Received: from [192.168.1.3] (pool-68-161-122-227.ny325.east.verizon.net [68.161.122.227]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by pi.codefab.com (Postfix) with ESMTP id 255F65DDA; Thu, 17 Nov 2005 15:04:36 -0500 (EST) Message-ID: <437CE254.3080701@mac.com> Date: Thu, 17 Nov 2005 15:04:36 -0500 From: Chuck Swiger Organization: The Courts of Chaos User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.12) Gecko/20050915 X-Accept-Language: en-us, en MIME-Version: 1.0 To: "Marc G. Fournier" References: <20051117150323.U1019@ganymede.hub.org> In-Reply-To: <20051117150323.U1019@ganymede.hub.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: amavisd-new at codefab.com Cc: freebsd-questions@freebsd.org Subject: Re: EM64T supported? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 17 Nov 2005 20:04:38 -0000 Marc G. Fournier wrote: > First off, what is it? On 32bit platforms, to address >4G of RAM, I > recall that there is some sort of 'paging' that has to be done to > address it ... does EM64T get around that somehow, or is this just > another name for it? EM64T uses 64-bit wide registers and addressing, and can talk to >4GB of RAM natively. Older processors may still support >4GB of physical RAM using the PSE/PSE-36 CPU extensions, but are still using 32-bit registers. -- -Chuck