If your Rift disconnect problem only occurs in DCS world, try moving power hungry USB devices (lighted HOTAS, RGB keyboards, etc.) to a powered USB hub rather than plugging them directly into front/back USB ports.
I noticed all of the llights on my HOTAS Warthog throttle go off at the same time my Rift disconnects. This revealed that ALL of my PC's USB ports were shutting off - apparently because too much current was required for all of my devices.
Since plugging my power hungry USB devices into a powered USB hub I have not had a single "Rift disconnect".
Hopefully this helps someone else. What a rellief!
