<html>
<head>
<base href="https://bugs.freedesktop.org/" />
</head>
<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Priority</th>
<td>medium
</td>
</tr>
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - Intel HD4400 Graphic (integrated with Haswell): detection of Dell U3011 monitor randomly fails"
href="https://bugs.freedesktop.org/show_bug.cgi?id=81816">81816</a>
</td>
</tr>
<tr>
<th>CC</th>
<td>intel-gfx-bugs@lists.freedesktop.org
</td>
</tr>
<tr>
<th>Assignee</th>
<td>intel-gfx-bugs@lists.freedesktop.org
</td>
</tr>
<tr>
<th>Summary</th>
<td>Intel HD4400 Graphic (integrated with Haswell): detection of Dell U3011 monitor randomly fails
</td>
</tr>
<tr>
<th>QA Contact</th>
<td>intel-gfx-bugs@lists.freedesktop.org
</td>
</tr>
<tr>
<th>Severity</th>
<td>normal
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr>
<tr>
<th>OS</th>
<td>Linux (All)
</td>
</tr>
<tr>
<th>Reporter</th>
<td>mathieu.desnoyers@efficios.com
</td>
</tr>
<tr>
<th>Hardware</th>
<td>x86-64 (AMD64)
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Version</th>
<td>unspecified
</td>
</tr>
<tr>
<th>Component</th>
<td>DRM/Intel
</td>
</tr>
<tr>
<th>Product</th>
<td>DRI
</td>
</tr></table>
<p>
<div>
<pre>Created <span class=""><a href="attachment.cgi?id=103554" name="attach_103554" title="kernel dmesg when screen stuck at 1024x768">attachment 103554</a> <a href="attachment.cgi?id=103554&action=edit" title="kernel dmesg when screen stuck at 1024x768">[details]</a></span>
kernel dmesg when screen stuck at 1024x768
External monitor misbehaving intermittently with a Lenovo x240, docked
into an UltraDock, with Dell U3011 connected in the UltraDock
displayport, when booting the machine and starting a X session, as well
as when going back from sleep.
Sometimes, the monitor is just blank. Sometimes, I need to power down
the monitor, unplug its AC for a few minutes, and plug it back again
(and restart the computer) before it starts working again. Sometimes
unplugging the DisplayPort connector from the UltraDock and plugging it
into the second DP helps.
Currently, the behavior is slightly different: it is stuck at a low
resolution (1024x768), as reported by xrandr (even though after a few reboots,
screen power cycles, and swapping the DP port, I'm eventually able to bring the
screen to its native 2560x1600 resolution).
I own 2 Dell U3011 monitors, and 2 Lenovo UltraDock, and each setup have
very similar issues with the same laptop.
Tested on a 3.15.6 Linux kernel.
ii xserver-xorg-video-intel 2:2.21.15-2+b2
I'm providing extra info within files attached to this bug report.
Please let me know if I can provide more info,
Thanks,
Mathieu</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are the QA Contact for the bug.</li>
<li>You are on the CC list for the bug.</li>
<li>You are the assignee for the bug.</li>
</ul>
</body>
</html>