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        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - Unable to connect 4K display FIFO underrun on pipe C."
   href="https://bugs.freedesktop.org/show_bug.cgi?id=92175">92175</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Unable to connect 4K display FIFO underrun on pipe C.
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>DRI
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>unspecified
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>Other
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>All
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>medium
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>DRM/Intel
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>intel-gfx-bugs@lists.freedesktop.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>amatcama@gmail.com
          </td>
        </tr>

        <tr>
          <th>QA Contact</th>
          <td>intel-gfx-bugs@lists.freedesktop.org
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>intel-gfx-bugs@lists.freedesktop.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Hi,
 I am using a Lenovo Thinkpad t540p running ArchLinux (so most likely running
latest version of intel driver). I have a docking station and am trying to
connect a Dell P2415Q monitor to it through DP. Using xrandr or arandr, I can
see that the monitor is successfully detected but when I enable it, although it
says that the monitor is enabled, I don't see any output on the screen and I
get the following in dmesg:
[drm:intel_set_cpu_fifo_underrun_reporting [i915]] *ERROR* uncleared fifo
underrun on pipe C
[drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe C FIFO
underrun
When I enable MST on the monitor however, it seems to work. But using MST this
monitor cannot run at 60hz.
Any clues on what the issue could be ?</pre>
        </div>
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