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

        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW --- - Strange readout on fan1_input when pwm1_min < 33"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=79820">79820</a>
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>nouveau@lists.freedesktop.org
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Strange readout on fan1_input when pwm1_min < 33
          </td>
        </tr>

        <tr>
          <th>QA Contact</th>
          <td>xorg-team@lists.x.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>freedesk.apriori@spamgourmet.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>Driver/nouveau
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>xorg
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=100705" name="attach_100705" title="jountalctl -b -k|grep nouveau">attachment 100705</a> <a href="attachment.cgi?id=100705&action=edit" title="jountalctl -b -k|grep nouveau">[details]</a></span>
jountalctl -b -k|grep nouveau

When running the drivers from kernel 3.15.0, pwm1_min seems to default to 35. I
noticed that this yields reported ~2k RPM in fan1_input for my card. Since the
fan runs at ~1k RPM in idle when running the NVIDIA blob, I tried lowering
pwm1_min and noticed odd results.

Lowering pwm1_min to 32 is fine and gives me a readout of ~1.8k RPM. However,
after that, I see weird output values:

31 ~ 4.5k
30 ~ 9k
29 ~ 5k
28 ~ 22k (sic)
27 ~ 75k (sic)
26 ~ 400k (sic)

At no time was my computer lifting up from the ground though, and even with the
reported 4.5k it seems that the fan did not actually speed up.

Additional background: It seems my fan is only supported as of Linux 3.15.0.
Before that, the fan ran at 100% and dmesg showed «FAN control: none /
external». On IRC I was informed that a new fan has been added to 3.15, and
indeed it seems to be recognized now (many thanks for that!).

I’m attaching my dmesg and my vbios in case it helps. Note though that
nvagetbios reported a warning when dumping the BIOS:

<span class="quote">> No extraction method specified (using -s extraction_method). Defaulting to PRAMIN.
> Attempt to extract the vbios from card 0 (nve6) using PRAMIN
> Invalid signature(0x55aa). You may want to try another retrieval method.</span >

Let me know if there’s additional information I could supply.</pre>
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