title: switch cuda compute mode to default mode
body: <p>I use <code>nvidia-smi</code> to see the status of each GPU on a computing node but find one of them is <code>E. Thread</code>. Is there any easy way to switch it back to <code>default mode?</code> 
  <code>
  ------------------------------------------------------+<br>
  | NVIDIA-SMI 346.46     Driver Version: 346.46         |<br>
  |-------------------------------+----------------------+----------------------+
  | GPU  Name        Persistence-M| Bus-Id        Disp.A | Volatile Uncorr. ECC |
  | Fan  Temp  Perf  Pwr:Usage/Cap|         Memory-Usage | GPU-Util  Compute M. |
  |===============================+======================+======================|
  |   0  GeForce GTX 680     Off  | 0000:03:00.0     N/A |                  N/A |
  | 30%   30C    P8    N/A /  N/A |     10MiB /  4095MiB |     N/A    E. Thread |
  +-------------------------------+----------------------+----------------------+
  |   1  GeForce GTX 680     Off  | 0000:04:00.0     N/A |                  N/A |
  | 30%   29C    P8    N/A /  N/A |     10MiB /  4095MiB |     N/A      Default |
  +-------------------------------+----------------------+----------------------+
  </code></p>