title: How can I run pytorch with multiple graphic cards?
body: <p>I have 4 graphic cards which I want to utilize to pytorch.
  I have this net:</p>
  
  <pre><code>class Net(nn.Module):
      def __init__(self):
          super(Net, self).__init__()
          self.conv1 = nn.Conv2d(1, 20, 5, 1)
          self.conv2 = nn.Conv2d(20, 50, 5, 1)
          self.fc1 = nn.Linear(4*4*50, 500)
          self.fc2 = nn.Linear(500, 10)
  
      def forward(self, x):
          x = F.relu(self.conv1(x))
          x = F.max_pool2d(x, 2, 2)
          x = F.relu(self.conv2(x))
          x = F.max_pool2d(x, 2, 2)
          x = x.view(-1, 4*4*50)
          x = F.relu(self.fc1(x))
          x = self.fc2(x)
          return F.log_softmax(x, dim=1)
  </code></pre>
  
  <p>How can I use them on this net?</p>