From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753841AbYHMUny (ORCPT ); Wed, 13 Aug 2008 16:43:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752684AbYHMUnm (ORCPT ); Wed, 13 Aug 2008 16:43:42 -0400 Received: from www.church-of-our-saviour.org ([69.25.196.31]:44768 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752701AbYHMUnm (ORCPT ); Wed, 13 Aug 2008 16:43:42 -0400 Date: Wed, 13 Aug 2008 16:43:38 -0400 From: Theodore Tso To: Henrique de Moraes Holschuh Cc: Pavel Machek , kernel list Subject: Re: 2.6.26: thinkpad x60 is cooled passively Message-ID: <20080813204338.GA6142@mit.edu> Mail-Followup-To: Theodore Tso , Henrique de Moraes Holschuh , Pavel Machek , kernel list References: <20080813080618.GA16061@elf.ucw.cz> <20080813152431.GD8232@mit.edu> <20080813203137.GB27546@khazad-dum.debian.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080813203137.GB27546@khazad-dum.debian.net> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@mit.edu X-SA-Exim-Scanned: No (on thunker.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 13, 2008 at 05:31:37PM -0300, Henrique de Moraes Holschuh wrote: > > know the fans have a tendency to go bad within 12-18 months, and so > > the CPU heat sink and fan unit needs to be replaced perdiocially. > > What does /proc/acpi/ibm/fan report? > > ThinkPad fans have a overdesign range of about 2x, they almost never stop > because they're too old. Clogged in dirt, on the other hand... a clogged > fan often spins FASTER and cools less. > > Want to see how much your fan has as far as a safety margin goes? use > thinkpad-acpi to measure RPMs in level 7 and also when you switch PWM off > (i.e. set it to 100% duty cycle). Mine gets faster by 1500RPM or so that > reflects the extra torque the EC can apply to get the fan to run at the > speed it wants it to. Hmm, maybe I've just had bad luck, or I live in a very dusty environment (four cats, including two longhairs in perma-shed mode, will do that to any house), but I've had at least 3 fan failures in the past 5-6 years where the fan stopped entirely, and had to be replaced. When I took it out, it was quite dirty, but the way it spun why I tried moving the fan blades with my finger, it felt just like the failure modes I've had with standard power supply fans that have gone bad due to old age. - Ted