From owner-freebsd-mobile Wed Aug 5 00:06:20 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id AAA29098 for freebsd-mobile-outgoing; Wed, 5 Aug 1998 00:06:20 -0700 (PDT) (envelope-from owner-freebsd-mobile@FreeBSD.ORG) Received: from awfulhak.org (awfulhak.demon.co.uk [158.152.17.1]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id AAA28998 for ; Wed, 5 Aug 1998 00:06:02 -0700 (PDT) (envelope-from brian@Awfulhak.org) Received: from gate.lan.awfulhak.org (brian@localhost [127.0.0.1]) by awfulhak.org (8.8.8/8.8.8) with ESMTP id IAA12582; Wed, 5 Aug 1998 08:02:34 +0100 (BST) (envelope-from brian@gate.lan.awfulhak.org) Message-Id: <199808050702.IAA12582@awfulhak.org> X-Mailer: exmh version 2.0.2 2/24/98 To: Mike Smith cc: Brian Somers , Randy Philipp , Doug White , Greg Lehey , freebsd-mobile@FreeBSD.ORG, "Jeroen van den Boom" Subject: Re: Neomagic chipset - is it a hardware problem ? In-reply-to: Your message of "Tue, 04 Aug 1998 07:24:15 PDT." <199808041424.HAA00456@antipodes.cdrom.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Wed, 05 Aug 1998 08:02:33 +0100 From: Brian Somers Sender: owner-freebsd-mobile@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org [Jeroen van den Boom from CTX cc'd - this may interest you!] [Greg cc'd - there's a question/request near the end... :-)] It looks like you're at least partially correct Mike. I've done some more tests with heating up, cooling down, restarting X, restarting FreeBSD, suspend & resume and LCD off & on.... It seems that the screen corruption is due to a combination of the X server initialisation (*not* doing something it should) and the heat of the machine. If I start X and let the machine heat up, or start X when the machine is already hot, I get the flickering. Once it's flickering, the display can be made crystal clear again by either suspending 'till the machine cools down (as I said before) or by simply switching the LCD off and on (there's a small switch for detecting when the lid is down that switches the LCD off by default and can be configured to make the laptop ``sleep''). If I ``sleep 'till cool'', the problem re-occurs as the machine heats up again. I can only guess that the sleep/resume is being caught by the power management stuff and X is re-initialising (wrongly) the display whereas the LCD off/on event is completely transparent and the laptop firmware knows how to make the screen work when hot..... once this `tweak' has happened, the display is fine forever more - up until it goes into text mode and back into graphics mode (ala X server). This is *very* peculiar, but I think it's now looking more like a software thing. I'll continue to test things.... I'm now running KDE 1.0 (window manager) and am using a screensaver - maybe this is relevant. I *do* wish NeoMagic would just publish the damn specs :-( The other ``weird'' thing is that nobody else seems to have reported this problem, although I guess there aren't that many that have gone to the trouble of manually merging the initialisation code, and even fewer (if any) that have a CTX Cybernote. Greg, as you've got a similar setup (although I doubt your machine is a CTX Cybernote), can you try doing a ``make world'' and see if you get similar behaviour, making sure that you *haven't* let the laptops LCD initialise itself (X should be the last thing to have set up the display from text mode) ? It would be much appreciated. Thanks everyone for your help. > > I've found out more about this flickering problem.... it only occurs > > when the laptop is physically warm - the warmer, the more flickering. > > If the machine sleeps for ~15 minutes, it'll wake up with a perfect > > picture and that picture will start to deteriorate with the building > > heat. If I switch the display off for 15 minutes it makes no > > difference. > > > > This is all under load. If the machine is idle it lasts a lot > > longer (the fan is more effective I guess....) > > > > Has anyone else seen this problem ? I'm pretty much convinced that > > it's a hardware problem now, so I'll probably return the machine > > (second time) nearer the end of the week. > > I've seen similar symptoms on a Toshiba using the C&T 65555. The part > would misbehave so badly that the X server would crash. > > Windows worked OK on it though; my hypothesis was just that the X > driver wasn't doing whatever power management stuff the Windows driver > was, and so the chip was overheating. I could be way off on that > though; I know nothing about the C&T architecture. > > -- > \\ Sometimes you're ahead, \\ Mike Smith > \\ sometimes you're behind. \\ mike@smith.net.au > \\ The race is long, and in the \\ msmith@freebsd.org > \\ end it's only with yourself. \\ msmith@cdrom.com -- Brian , , Don't _EVER_ lose your sense of humour.... To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-mobile" in the body of the message