I just wanted to add that I did a little experiment with drivers with the latest release.
0.5.7 is unstable with NVidia 388.xx drivers. It instant crashes for me and never restarts. I want to add that new games like PUBG did the same.
So I tried older drivers, I found that 384.94 works flawless with 0.5.7 and earlier release + I got increased hashrate compared to 388.xx drivers.
This was tested for my 3 rigs with 1080ti and 1070 on windows 10 with latest updates.
I'm using the latest 388.xx drivers on windows 10 with a mix of 1070 and 1070ti and it's been running for days without a hitch.
Weird that different people have such different outcomes.