Why is my GPU slower than CPU when training LSTM/RNN models?

Question

My machine has the following spec:

CPU: Xeon E5-1620 v4

GPU: Titan X (Pascal)

Ubuntu 16.04

Nvidia driver 375.26

CUDA tookit 8.0

Answer 1

It's just a tip.

Using GPU is powerful when

1. your neural network model is big.
2. batch size is big.

It's what I found from googling.