title: Tensorflow installation using SSE instructions with pip
body: <p>I successfully installed cpu only tensorflow on ubuntu 16.04 using the default instructions provided <a href="https://www.tensorflow.org/install/install_linux#installing_with_virtualenv" rel="noreferrer">here</a>. The instructions recommended using virtualenv and pip so I did not build from source. I had no problems installing with these instructions.</p>
  <p>I validated my installation using the instructions provided <a href="https://www.tensorflow.org/install/install_linux#validate_your_installation" rel="noreferrer">further down</a> on the same page, and while the program ran successfully, it output the following warnings.</p>
  <pre><code>W tensorflow/core/platform/cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use SSE3 instructions, but these are available on your machine and could speed up CPU computations.
  W tensorflow/core/platform/cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use SSE4.1 instructions, but these are available on your machine and could speed up CPU computations.
  W tensorflow/core/platform/cpu_feature_guard.cc:45] The TensorFlow library wasn't compiled to use SSE4.2 instructions, but these are available on your machine and could speed up CPU computations.
  Hello, TensorFlow!
  </code></pre>
  <p>all the stackoverflow pages i've looked at only address people who have built from source using bazel, but don't seem to apply to people who used pip.</p>
  <p>How do I recompile or update my installation so as to the SSE instructions?</p>