Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261171AbTEMMb5 (ORCPT ); Tue, 13 May 2003 08:31:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261179AbTEMMb5 (ORCPT ); Tue, 13 May 2003 08:31:57 -0400 Received: from kunde0838.tromso.alfanett.no ([62.16.131.79]:59872 "EHLO shogun") by vger.kernel.org with ESMTP id S261171AbTEMMbz (ORCPT ); Tue, 13 May 2003 08:31:55 -0400 Message-ID: <3EC0E885.9070306@thule.no> Date: Tue, 13 May 2003 14:43:49 +0200 From: Troels Walsted Hansen User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.3.1) Gecko/20030425 X-Accept-Language: en MIME-Version: 1.0 To: Andrew McGregor CC: Tuncer M zayamut Ayaz , linux-kernel@vger.kernel.org Subject: Re: 2.5.69 strange high tone on DELL Inspiron 8100 References: <1405.1052575075@www9.gmx.net> <3191078.1052695705@[192.168.1.249]> In-Reply-To: <3191078.1052695705@[192.168.1.249]> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1521 Lines: 46 Andrew McGregor wrote: > Try this (which will make no difference to the effectiveness of APM on > this machine): > >> CONFIG_PM=y >> >> CONFIG_APM=y >> CONFIG_APM_DO_ENABLE=n >> CONFIG_APM_CPU_IDLE=n >> CONFIG_APM_DISPLAY_BLANK=y >> CONFIG_APM_REAL_MODE_POWER_OFF=y >> >> CONFIG_CPU_FREQ=n >> CONFIG_CPU_FREQ_TABLE=n >> >> CONFIG_X86_SPEEDSTEP=n > > > Reasoning: > cpufreq and speedstep don't work on Dell P3 laptops anyway, and the > *internal power supplies* of the i8x00 series make wierd noises when APM > tries to idle the CPU. The board will do this anyway, without making > noise, so linux need not. My Dell Latitude C600 shows the exact same problem. I noticed it after upgrading to from RH7.x to RH8 with kernel 2.4.18-27.8.0. I believe this kernel is customized by RH to use HZ=500 or something in that region. With your analysis of the problem I was able to remove the noise by using the "apm=idle-threshold=100" parameter on the kernel commandline. This turns off APM idle calls without requiring kernel recompilation. Using the "i8k" kernel module, I have verified that the temperature of the CPU is unchanged with APM idle turned off. I have not tried to measure power consumption or battery use. Thanks for the tip! -- Troels Walsted Hansen - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/