Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 9 Mar 2001 21:11:09 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 9 Mar 2001 21:10:59 -0500 Received: from monolith.eradicator.org ([64.81.135.24]:37542 "EHLO localhost") by vger.kernel.org with ESMTP id ; Fri, 9 Mar 2001 21:10:49 -0500 To: linux-kernel@vger.kernel.org Subject: Re: [PATCH]: allow notsc option for buggy cpus In-Reply-To: From: David Huggins-Daines Organization: None worth mentioning Date: 09 Mar 2001 21:09:47 -0500 In-Reply-To: Alan Cox's message of "Sat, 10 Mar 2001 01:23:37 GMT" Message-ID: <877l1yxtlg.fsf@monolith.eradicator.org> Lines: 23 User-Agent: Gnus/5.0803 (Gnus v5.8.3) Emacs/20.7 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Alan Cox writes: > > My IBM Thinkpad 600E changes between 100MHz and 400MHz depending if the > > power is on. This means gettimeofday goes backwards if you boot with the > > Intel speedstep CPU. The 600E's CPU doesn't actually use SpeedStep (it's only a 400MHz Mobile Pentium2, SpeedStep made its debut with the 600MHz Mobile Pentium3), but rather some kind of external speed throttling... which accomplishes basically the same thing, and makes one wonder why Intel had to go and trademark the idea of incorporating it into the CPU. Toshiba laptops and probably others have been doing the same thing for ages now, I once had a Tecra (now sadly deceased) that would throttle from 133MHz to 66MHz (I think) when unplugged. I think this behaviour can be controlled with tpctl for the Thinkpads and possibly with the Toshiba utils on Toshibas... -- David Huggins-Daines - dhd@pobox.com http://www.pobox.com/~dhd/ - 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/