README.md in ruby-dnn-1.1.6 vs README.md in ruby-dnn-1.2.0

- old
+ new

@@ -93,11 +93,11 @@
 | Pooling | MaxPool2D, AvgPool2D, GlobalAvgPool2D, UnPool2D |
 | Optimizers | SGD, Nesterov, AdaGrad, RMSProp, AdaDelta, RMSPropGraves, Adam, AdaBound |
 | Losses | MeanSquaredError, MeanAbsoluteError, Hinge, HuberLoss, SoftmaxCrossEntropy, SigmoidCrossEntropy |
 
 ## Datasets
-By setting the environment variable "RUBY_DNN_DOWNLOADS_PATH", you can specify the path to read dataset.
+By setting the environment variable 'RUBY_DNN_DOWNLOADS_PATH', you can specify the path to read dataset.
 
 ● Iris  
 ● MNIST  
 ● Fashion-MNIST  
 ● CIFAR-10  
@@ -107,13 +107,17 @@
 ## Examples
 ● VAE  
 ● DCGAN  
 ● Pix2pix
 
+## Use GPU
+If you do 'require "cumo/narray"' before 'require "dnn"', you can run it on GPU.
+Or, set the environment variable 'RUBY_DNN_USE_CUMO 'to'ENABLE' to force the GPU to be used.
+
 ## TODO
 ● Write a test.  
 ● Write a document.  
-● Support to GPU.  
+● Improve performance when using GPU.  
 
 ## Development
 
 After checking out the repo, run `bin/setup` to install dependencies. Then, run `rake "spec"` to run the tests. You can also run `bin/console` for an interactive prompt that will allow you to experiment.
 