title: Although pc recognizes gpu, it uses a CPU in tensorflow-gpu
body: <p>I am using tensorflow-gpu.  I want to use GTX1070, but tensorflow-gpu uses my CPU.  I don't know　what to do.</p>
  
  <p>I use CUDA 9.0 and CUDNN 7.1.4. My tensorflow-gpu version is 1.9.</p>
  
  <p>After running this command on the official website</p>
  
  <pre><code>&gt;&gt;&gt; import tensorflow as tf
  &gt;&gt;&gt; hello = tf.constant('Hello, TensorFlow!')
  &gt;&gt;&gt; sess = tf.Session()
  </code></pre>
  
  <blockquote>
    <p>2018-07-30 10:53:43.369025: I
    T:\src\github\tensorflow\tensorflow\core\platform\cpu_feature_guard.cc:141]
    Your CPU supports instructions that this TensorFlow binary was not
    compiled to use: AVX2 2018-07-30 10:53:43.829922: I
    T:\src\github\tensorflow\tensorflow\core\common_runtime\gpu\gpu_device.cc:1392]
    Found device 0 with properties: name: GeForce GTX 1070 major: 6 minor:
    1 memoryClockRate(GHz): 1.683 pciBusID: 0000:01:00.0 totalMemory:
    8.00GiB freeMemory: 6.63GiB 2018-07-30 10:53:43.919043: I T:\src\github\tensorflow\tensorflow\core\common_runtime\gpu\gpu_device.cc:1392]
    Found device 1 with properties: name: GeForce GTX 1050 major: 6 minor:
    1 memoryClockRate(GHz): 1.455 pciBusID: 0000:05:00.0 totalMemory:
    2.00GiB freeMemory: 1.60GiB 2018-07-30 10:53:43.926001: I T:\src\github\tensorflow\tensorflow\core\common_runtime\gpu\gpu_device.cc:1456]
    Ignoring visible gpu device (device: 1, name: GeForce GTX 1050, pci
    bus id: 0000:05:00.0, compute capability: 6.1) with Cuda
    multiprocessor count: 5. The minimum required count is 8. You can
    adjust this requirement with the env var
    TF_MIN_GPU_MULTIPROCESSOR_COUNT. 2018-07-30 10:53:43.934810: I
    T:\src\github\tensorflow\tensorflow\core\common_runtime\gpu\gpu_device.cc:1471]
    Adding visible gpu devices: 0 2018-07-30 10:53:44.761551: I
    T:\src\github\tensorflow\tensorflow\core\common_runtime\gpu\gpu_device.cc:952]
    Device interconnect StreamExecutor with strength 1 edge matrix:
    2018-07-30 10:53:44.765678: I
    T:\src\github\tensorflow\tensorflow\core\common_runtime\gpu\gpu_device.cc:958]
    0 1 2018-07-30 10:53:44.768363: I
    T:\src\github\tensorflow\tensorflow\core\common_runtime\gpu\gpu_device.cc:971]
    0:   N N 2018-07-30 10:53:44.771773: I
    T:\src\github\tensorflow\tensorflow\core\common_runtime\gpu\gpu_device.cc:971]
    1:   N N 2018-07-30 10:53:44.774913: I
    T:\src\github\tensorflow\tensorflow\co<code>enter code
    here</code>re\common_runtime\gpu\gpu_device.cc:1084] Created TensorFlow
    device (/job:localhost/replica:0/task:0/device:GPU:0 with 6395 MB
    memory) -> physical GPU (device: 0, name: GeForce GTX 1070, pci bus
    id: 0000<code>enter code here</code>:01:00.0, compute capability: 6.1)</p>
  </blockquote>