Hashrate drop and stay N/A
I'm running the same file setting on 4 PCs. However on my 2 PCs that are running windows server 2016 the hashrate starts very high then suddenly become n/a, it's not consistent, sometime i could just restart it and it runs again but sometime it takes a day for me to have it run again. I have another PC that is running windows server 2016 and sometime it drops but not like these 2 Pcs.

Please advice. thanks

![hashdrop](https://user-images.githubusercontent.com/29996277/34443487-573db946-ec7c-11e7-86b0-d297dd2a30ef.PNG)
