I have TWC (Time Warner Cable) as my ISP, they gave my mom this stuffty router and we had to pay an extra $15 every month onto the bill because of it, about a month or so ago I kept bothering her to get a new one because I play a lot of online gaming and downloading. The old router kept disconnecting me when I had too much traffic. I got a new router known as "Netgear C3700," I love this router and I wouldn't trade it for anything else right now. We no longer have to pay the $15 and I never get disconnected for handicapped limits.
Edit: What I am saying here, it might just be your router.