Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264169AbUD2Lyt (ORCPT ); Thu, 29 Apr 2004 07:54:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264155AbUD2Lyt (ORCPT ); Thu, 29 Apr 2004 07:54:49 -0400 Received: from jurand.ds.pg.gda.pl ([153.19.208.2]:33740 "EHLO jurand.ds.pg.gda.pl") by vger.kernel.org with ESMTP id S264182AbUD2Lys (ORCPT ); Thu, 29 Apr 2004 07:54:48 -0400 Date: Thu, 29 Apr 2004 13:54:46 +0200 (CEST) From: "Maciej W. Rozycki" To: Ross Dickson Cc: Jesse Allen , Len Brown , a.verweij@student.tudelft.nl, "Prakash K. Cheemplavam" , Craig Bradney , christian.kroener@tu-harburg.de, linux-kernel@vger.kernel.org, Jamie Lokier , Daniel Drake , Ian Kumlien , Allen Martin Subject: Re: IO-APIC on nforce2 [PATCH] + [PATCH] for nmi_debug=1 + [PATCH] for idle=C1halt, 2.6.5 In-Reply-To: <200404292144.37479.ross@datscreative.com.au> Message-ID: References: <200404282133.34887.ross@datscreative.com.au> <20040428205938.GA1995@tesore.local> <200404292144.37479.ross@datscreative.com.au> Organization: Technical University of Gdansk 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 Content-Length: 1807 Lines: 31 On Thu, 29 Apr 2004, Ross Dickson wrote: > > Do you really think so? I think there may be a resonance occuring, even with > > this new BIOS. I plugged in new headphones into my nforce2 onboard sound, and > > get a high pitched noise. Now here is where it gets weird: This noise does > > not occur on boot until sometime after the IDE driver is loaded. I also > > believe it varies under a high load. If you disable C1 disconnect, it's gone. > > Also I've heard a high pitched noise at certain times coming right from the > > copmuter (very faint, but I do have very good hearing, I can even hear a hush > > sounding from my router. my brother was quite astonished when I pointed that > > out) I try to distinguish whats doing it. It could be the hard drive. But > > when I found the other sound in the head phones, I found that the sound varies > > almost in unison with the sound coming from the computer. Maybe the IDE or > > hard drive is related, but it is too much related to C1 disconnect. > > I think I might break out my oscilloscope this weekend and have a look at how > clean the supply rails are around the cpu and northbridge and southbridge. > Who knows I might get lucky and see some unexpected ripple or spikes. Not necessarily related to the PSU, but the noise may actually be the reason of spurious timer interrupts. -- + Maciej W. Rozycki, Technical University of Gdansk, Poland + +--------------------------------------------------------------+ + e-mail: macro@ds2.pg.gda.pl, PGP key available + - 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/