I have a similar problem too, even when connected via ethernet with wifi off? it always says "connected" but just won't load up any pages, either via my home broadband or via my personal hotspot on mobile. definitely my system has other devices are fine. I've searched this forum for solutions and for the last hour or so suffered no drops by changing the "bandwidth capability" to 20/40MHz in the device manager settings. touch wood this may have solved it, though not counting my chickens yet.
My WiFi connection keeps dropping in every five minutes, i have to disconnect and then reconnect to resolve the issue but then after five minutes it drops again and a small exclamation sign appears on the WiFi bar. I'm using a dell inspiron SE 7520. this problem started happening when i updated my pc to windows 8.1. I have tried to solve the issue by updating the driver  changing the wireless settings and also updating the bios but nothing seems to work.
WiFi keeps dropping in every five mins!