diff --git a/README.md b/README.md
index 449288f..f1e9cf3 100644
--- a/README.md
+++ b/README.md
@@ -94,9 +94,7 @@ Prediction is sampled after 110K iterations and I only implemented one-step trai
 * [Roboschool](https://github.com/openai/roboschool) (Optional)
 * PyTorch v0.3.0
 * Python 2.7 or Python 3.6
-* Tensorflow (Optional, but tensorboard is awesome)
-> If you want to use Roboschool, you have to use Python3. And don't try to use Roboschool with parallelized algorithms,
-> there is a known [critical bug](https://github.com/openai/roboschool/issues/86).
+* [TensorboardX](https://github.com/lanpa/tensorboard-pytorch)
 
 
 # Usage
diff --git a/utils/tf_logger.py b/utils/tf_logger.py
index 600dd0a..72e2905 100644
--- a/utils/tf_logger.py
+++ b/utils/tf_logger.py
@@ -22,4 +22,4 @@ class Logger(object):
     def histo_summary(self, tag, values, step):
         if self.skip:
             return
-        self.writer.add_histogram(tag, values, step)
\ No newline at end of file
+        self.writer.add_histogram(tag, values, step, bins=1000)
\ No newline at end of file