From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030651AbXDPORy (ORCPT ); Mon, 16 Apr 2007 10:17:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030653AbXDPORy (ORCPT ); Mon, 16 Apr 2007 10:17:54 -0400 Received: from hp3.statik.TU-Cottbus.De ([141.43.120.68]:59996 "EHLO hp3.statik.tu-cottbus.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030651AbXDPORx (ORCPT ); Mon, 16 Apr 2007 10:17:53 -0400 Message-ID: <46238572.5050203@s5r6.in-berlin.de> Date: Mon, 16 Apr 2007 16:17:22 +0200 From: Stefan Richter User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.8.1.2) Gecko/20070222 SeaMonkey/1.1.1 MIME-Version: 1.0 To: Jeff Chua CC: linux-kernel@vger.kernel.org Subject: Re: 4GB Physical. Less than 3GB in Linux. References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jeff Chua wrote: > I've noticed that with 4GB physical ram, I'm only see 3098000 MB on > the Dell 745, and 3107056MB on the IBM X60s. > > I've tested with CONFIG_HIGHMEM4G=y, CONFIG_HIGHMEM64G=y, > CONFIG_X86_PAE=y, but nothing makes any difference. > > Tested on Linux 2.6.20, Linux 2.6.21-rc7. The X60 most certainly contains a chipset which severely limits the amount of accessible RAM due to issues with remapping of PCIe addresses. Intel explains it somewhere on their web presence. A quick & lazy web search turned this Intel paper up: http://www.polywell.com/us/support/faq/4GB_Rev1.pdf -- Stefan Richter -=====-=-=== -=-- -==-= http://arcgraph.de/sr/