From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([208.92.234.80] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1Qgpn5-0007xj-Q4 for garchives@archives.gentoo.org; Wed, 13 Jul 2011 03:07:16 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id C24D721C0FE for ; Wed, 13 Jul 2011 03:07:09 +0000 (UTC) Received: from mailout-de.gmx.net (mailout-de.gmx.net [213.165.64.22]) by pigeon.gentoo.org (Postfix) with SMTP id 1C0AAE0693 for ; Wed, 13 Jul 2011 02:27:18 +0000 (UTC) Received: (qmail invoked by alias); 13 Jul 2011 02:27:18 -0000 Received: from p54851412.dip0.t-ipconnect.de (EHLO gmx.net) [84.133.20.18] by mail.gmx.net (mp072) with SMTP; 13 Jul 2011 04:27:18 +0200 X-Authenticated: #20088476 X-Provags-ID: V01U2FsdGVkX1/PSjgsnVjPal7Rlpi8dRRcxlMMQSzzgXrgopMIjI bcoxI3BCWBA/62 Received: by gmx.net (nbSMTP-1.00) for uid 1001 Meino.Cramer@gmx.de; Wed, 13 Jul 2011 04:27:18 +0200 (CEST) Date: Wed, 13 Jul 2011 04:27:17 +0200 From: meino.cramer@gmx.de To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] Problem with xf86-video-ati & nvidia-drivers Message-ID: <20110713022717.GA3026@solfire> References: <20110710002013.GB3068@solfire> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: User-Agent: mutt-ng/devel-r804 (Linux) X-Y-GMX-Trusted: 0 X-Archives-Salt: X-Archives-Hash: 5422eec11c6d5e97a963e27c0cbea1de Grant [11-07-13 03:13]: > >>> When I was using an Nvidia video card, I noticed a strange sort of > >>> fuzzy edge effect if I used nvidia-drivers. =A0xf86-video-nouveau did= n't > >>> have the same problem. =A0Now I've switched to an ATI video card and > >>> unfortunately I have the same problem with xf86-video-ati. =A0I tried= to > >>> enable the new modesetting radeon driver in the kernel to see if that > >>> would help but it doesn't work with my HD4250 card yet. =A0Does anyone > >>> know how to fix this? =A0Here's a photo of the effect around the mouse > >>> cursor: > >>> > >>> http://imageshack.us/photo/my-images/804/cursor.jpg > >>> > >>> - Grant > >>> > >> > >> Hi Grant, > >> > >> just a shot in the dark: > >> The image looks to me as thos would be an analog instead of > >> an digital problem. > >> May be both propietary drivers switch to the highest possible > >> data transfer rate and this triggers the problem. > >> To check, whether this may be the problem: > >> Instruct the driver to use either low resolution or low refresh > >> rates. Check both. > >> If the problem changes signifiently: Change the cables. > >> May be only a pluf is not inserted correctly. > >> Addtionally you can move the cables arround to see whether > >> this will change the shadows around the cursor in any way... > >> > >> Good luck! :) > >> Best regards > >> mcc > > > > Thanks for that. =A0I'm still working on it but adding radeon.audio=3D0= to > > grub cleaned it up about 75%. > > > > - Grant >=20 > It turns out the radeon.audio=3D0 setting disables HDMI data packets and > puts the HDMI port in DVI mode. mcc, I'm starting to think you had it > pretty right on. I've tried two different cables with the same result > but I'm thinking this may be some sort of electrical interference > issue. I deal with stuff like that in audio. There's a USB isolator > which cleans the sound way up when used with a USB sound card: >=20 > http://www.analog.com/en/interface/digital-isolators/adum4160/products/pr= oduct.html >=20 > Now I wish there was something like that for HDMI. >=20 > - Grant >=20 Hi Grant, another shot into an even much deeper dark .... ;) May be you have a problem here, which it is called "Brummschleife" in german...sorry dont know the English equivalent...may be something like "buzzing loop"...but this looks more like a strange translation=20 made by google than by any other, human being ;) Anyway.... A "Brummschleife" happens when doing something like this: +----+ +-----------+ --------------+ |-(1)----------------------+ monitor or|------------- mains | PC |-(2)----------------------| amplifier | mains = =20 --------------+ | (audio/USB/video or + or..... |------------- -+------------+----+ another low voltage +-----------+-----------+- = =20 | thingy) | = =20 (3) (4) | | = =20 _ _ = =20 ground groun= d =20 Normally all protective earth's connection should end in ONE point: A copper rod or someting like this. BUT often the wires between them are too long or there are two or even more end points. Result: HF from near by broadcast stations, 60Hz mains frequency, ham radio station, microwave ovens and anything which can emit energy, pushes protective earth to another electrical potential than 0V. Since both, PC and -- in your case -- the monitor are using protective earth, they may be put on "another", may be even varying (over time) electrical potentials. Since they are connected=20 via a two-wire connection WITHOUT protective earth (no, the shielding=20 is not for that purpose) the difference in the potential earth put=20 both ends to different electrical reference points. This way you get an amplitude modulation of the signal between both endpoint. In case of 60HZ you will hear a "Brummschleife" sound on audio connection (a buzzing sound), in case of frequencies near=20 those of the video signal you will get "ghosts" in the monitor picture. Now, how to avoid that. Hit the one who have made the protective earth connection in your house. While you are searching for that person, you can try the following: Put all mains connectors of you PC rig into ONE wall connector with something like this (ok I miss some words here again and=20 since a picture says more than even thousands of /missing/ words here comes an image of what I mean:): http://www.reichelt.de/Steckdosenleisten-ohne-Schalter/6-FACH-DOSE-WS-5/ind= ex.html?;ACTION=3D3;LA=3D2;ARTICLE=3D108651;GROUPID=3D4281;SID=3D11Thz@On8A= AAIAABaBBrE9f5418078c2ea9fe6608e9765d978595 This way, all protective earth ends up in the same contact. No differences in the electricla potential of the protective earth anymore. Why does the those USB-isolatore-like cables help here? These small air core transformers (or in other words: There is no core at all... ;) ) do a (german, sorry...) "Gleichtaktunterdrueckung" which means, that any potential difference (which is: the signal itsself) between wire (1) and wire (2) is transmitted, and any modulating=20 difference of electrical potential between (3) and (4), influencing (1) and (2) at the same time the same way will be suppressed by the transformers. Hopefully the theorectical aspect of this will not surpress the practical success here ;) Good luck! Best regards, mcc