title: Tensorflow: I installed CUDA 9.2 but it needs 9.0?
body: <p>I followed an instruction from a book and installed CUDA Toolkit version 9.2. Then I got this error</p>
  
  <blockquote>
    <p>ImportError: Could not find 'cudart64_90.dll'. TensorFlow requires that this DLL be installed in a directory that is named in your %PATH% environment variable. Download and install CUDA 9.0 from this URL: <a href="https://developer.nvidia.com/cuda-toolkit" rel="noreferrer">https://developer.nvidia.com/cuda-toolkit</a></p>
  </blockquote>
  
  <p>I searched and found that tensorflow needs 9.0, but what should I do next? Should I delete the old version of CUDA then install the 9.0 ver., or just install 9.0(so I would have two version co-existing)? I don't want to break my computer, help~~~</p>
  
  <p>Edit:</p>
  
  <p>I downloaded CUDA9.0 patch1 from the link: <a href="https://developer.nvidia.com/cuda-90-download-archive?target_os=Windows&amp;target_arch=x86_64&amp;target_version=10&amp;target_type=exelocal" rel="noreferrer">https://developer.nvidia.com/cuda-90-download-archive?target_os=Windows&amp;target_arch=x86_64&amp;target_version=10&amp;target_type=exelocal</a> . But it seems like the installer didn't work(it disappeared immediately when I double clicked it)?</p>