Author: branden
Date: 2004-07-14 15:14:36 -0500 (Wed, 14 Jul 2004)
New Revision: 1643
Modified:
trunk/debian/CHANGESETS
trunk/debian/changelog
trunk/debian/local/FAQ.xhtml
Log:
Add FAQ entry: I'm having trouble getting dual-head support to work on my
ATI Radeon card. Can you help? (Closes: #236197)
Modified: trunk/debian/CHANGESETS
===================================================================
--- trunk/debian/CHANGESETS 2004-07-14 17:31:53 UTC (rev 1642)
+++ trunk/debian/CHANGESETS 2004-07-14 20:14:36 UTC (rev 1643)
@@ -64,4 +64,8 @@
#255270)
1640
+Add FAQ entry: I'm having trouble getting dual-head support to work on my
+ATI Radeon card. Can you help? (Closes: #236197)
+ 1643
+
vim:set ai et sts=4 sw=4 tw=80:
Modified: trunk/debian/changelog
===================================================================
--- trunk/debian/changelog 2004-07-14 17:31:53 UTC (rev 1642)
+++ trunk/debian/changelog 2004-07-14 20:14:36 UTC (rev 1643)
@@ -46,8 +46,11 @@
suggestion of the libglide3 package (and explanation thereof) to the
xlibmesa-dri package.
- -- Branden Robinson <[EMAIL PROTECTED]> Wed, 14 Jul 2004 11:02:43 -0500
+ * Add FAQ entry: I'm having trouble getting dual-head support to work on my
+ ATI Radeon card. Can you help? (Closes: #236197)
+ -- Branden Robinson <[EMAIL PROTECTED]> Wed, 14 Jul 2004 11:38:17 -0500
+
xfree86 (4.3.0.dfsg.1-6) unstable; urgency=low
Changes by Branden Robinson:
Modified: trunk/debian/local/FAQ.xhtml
===================================================================
--- trunk/debian/local/FAQ.xhtml 2004-07-14 17:31:53 UTC (rev 1642)
+++ trunk/debian/local/FAQ.xhtml 2004-07-14 20:14:36 UTC (rev 1643)
@@ -146,6 +146,8 @@
failed for driver 0</q>. Is that why the X server won't start?</a></li>
<li><a href="#didservercrash">How can I tell if it's the X server crashing, or
my X session exiting abnormally?</a></li>
+<li><a href="#radeondualhead">I'm having trouble getting dual-head support to
+ work on my ATI Radeon card. Can you help?</a></li>
</ul>
<h2><a href="#acknowledgements">Acknowledgements</a></h2>
@@ -2584,11 +2586,55 @@
"'core pointer' ..."-question</a> above for more information on how to deal
with
this.</p>
+<h3><a id="radeondualhead">I'm having trouble getting dual-head support to work
+ on my ATI Radeon card. Can you help?</a></h3>
+
+<p><em>Thanks to Paul Gotch for writing most of this entry.</em></p>
+
+<p>Some users, particularly those who dual-boot GNU/Linux and one of the
+Microsoft Windows operating systems, find that their ATI Radeon cards appear to
+autodetect the presence of a second monitor differently depending on whether
the
+machine was brought up "cold" into GNU/Linux, or simply restarted from Windows.
+However, the advice in this section is intended for all dual-head ATI Radeon
+users.</p>
+
+<p>In your <code class="filename">/etc/X11/XF86Config-4</code> file, you may
+need to use the <code class="other">MonitorLayout</code> option in each of the
+<code class="other">Device</code> sections corresponding to the "heads"
+(monitors) being driven by the video card. This option is documented in the
+<code class="manpage">radeon(4x)</code> manual page.</p>
+
+<p>At system reset, the video card tries to determine what is connected to each
+of the ports. This is necessary because digital video output (DVI) is very
+different from analog video output (VGA).</p>
+
+<p>If a display is connected to the DVI port, that becomes the primary display,
+and the VGA port the secondary display. Otherwise, the VGA port is the primary
+and the DVI port is not enabled.</p>
+
+<p>If dual-head operation is then forcibly enabled when the video card doesn't
+think that there is anything connected to the second display, the secondary
head
+is driven in "clone mode". This is either undocumented behaviour, or is a
+default in the Radeon driver if the card has failed to autodected over the the
+DDC (Data Display Channel) connection to the monitor.</p>
+
+<p>In my case I believe the problem was caused by the presence of a KVM switch
+between the card and the monitor. DDC seems to be very flaky. <code
+class="other">:/</code></p>
+
+<p>The workaround of using the <code class="other">MonitorLayout</code> option
+simply forces the card into a particular mode so that it ignores whatever is
+comming over DDC.</p>
+
+<p>I've heard that it is possible to damage the card with an incorrect <code
+class="other">MonitorLayout</code> line, but I can't think of a physical
+mechanism for this actually happening.</p>
+
<h2><a id="acknowledgements">Acknowledgements</a></h2>
<p>The author would like to thank Andreas Metzler, Guillem Jover, Ingo Saitz,
Osamu Aoki, Matthew Arnison, Colin Walters, Steve Swales, Adam Jackson, Thomas
-Dickey, and "ulisses" for their contributions to this document.</p>
+Dickey, Paul Gotch, and "ulisses" for their contributions to this document.</p>
<hr />
<p class="x-small">$Id$</p>
