Tensorflow GPU Check

import tensorflow as tf

with tf.device('/gpu:0'):

      a = tf.constant([1.0, 2.0, 3.0, 4.0, 5.0, 6.0], shape=[2, 3], name='a')

      b = tf.constant([1.0, 2.0, 3.0, 4.0, 5.0, 6.0], shape=[3, 2], name='b')

      c = tf.matmul(a, b)

with tf.Session() as sess:

print(sess.run(c))