I just bought this router and have been having particular issues with the connection either restarting or turning off - this appears to primarily, if only, impact my Blizzard Game Launcher / games (it will disconnect me from games). Dropouts appear to range from a few minutes to up to 30-40min gametime before being disconnected. I don't appear to have issues with other internet usage. 

This appears to have only started upon using this router as when I plug in my old one (the one received from my ISP) the connection remains true through while gaming.

I'm loath do it it, because the wifi range gained from the C5400 has been awesome in the week since purchasing it, but among its primary reasons for being purchased was to assist in my gaming experience yet now it is hamstringing it completely and if it can't do that then I'll just have to return it.