From owner-freebsd-questions@freebsd.org Fri Jul 15 08:14:12 2016 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 253A8B994BE for ; Fri, 15 Jul 2016 08:14:12 +0000 (UTC) (envelope-from perryh@pluto.rain.com) Received: from agora.rdrop.com (agora.rdrop.com [IPv6:2607:f678:1010::34]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 0DD1717CF for ; Fri, 15 Jul 2016 08:14:11 +0000 (UTC) (envelope-from perryh@pluto.rain.com) Received: from agora.rdrop.com (66@localhost [127.0.0.1]) by agora.rdrop.com (8.13.1/8.12.7) with ESMTP id u6F8E79O080552 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Fri, 15 Jul 2016 01:14:07 -0700 (PDT) (envelope-from perryh@pluto.rain.com) Received: (from uucp@localhost) by agora.rdrop.com (8.13.1/8.14.2/Submit) with UUCP id u6F8E7D3080551; Fri, 15 Jul 2016 01:14:07 -0700 (PDT) (envelope-from perryh@pluto.rain.com) Received: from fbsd81 by pluto.rain.com (4.1/SMI-4.1-pluto-M2060407) id AA02381; Fri, 15 Jul 16 01:10:56 PDT Date: Fri, 15 Jul 2016 01:10:49 -0700 From: perryh@pluto.rain.com (Perry Hutchison) To: rvernica@gmail.com Cc: freebsd-questions@freebsd.org Subject: Re: x11: Primary monitor goes black randomly Message-Id: <57889a89.+gS26xnVFNwWE+uK%perryh@pluto.rain.com> References: In-Reply-To: User-Agent: nail 11.25 7/29/05 Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 15 Jul 2016 08:14:12 -0000 Rares Vernica wrote: > I am using an HP Elitebook 2560p which has an integrated Intel video card. > I use two external monitors, one connected on the DisplayPort as primary > and one on the VGA port as secondary. I am not using the built-in display. > > I use x11 with xfce and the Intel driver. It all works fine, except that > the the primary monitor (on the DisplayPort) goes black at random times. > Once black, the monitor reports no signal and goes on stand by. It does > not resume working if I move the mouse or type on the keyboard. One way I > managed to recover it is to turn the display off with xrandr and then back > on. I suspect this is an x11 problem, not a FreeBSD problem. I have been seeing something similar on a Dell laptop, using gnome, with the built-in display as primary and an external 1920x1080 flatscreen on a DVI port (on the docking station) as secondary. The primary occasionally goes blank just after logging in (via xdm), about the time when xrandr would be setting up the dual screens, and the only way I've found to bring it back is to tweak the screen positions slightly in gnome-control-center (which then presumably runs xrandr when I click Apply). I suspect a race condition since it happens only occasionally. So why do I think this is not a FreeBSD issue? Because it happens on Fedora Linux (at $DAYJOB).