Constant internet hiccups?

So out of the blue today the internet on my PC keeps cutting out, approx. twice a minute on average, for only a couple seconds at a time. I've restarted my PC, restarted the router, and changed which router port I'm plugged into. Changed which ethernet cables I'm using. I've tried everything. My roommate is having NO issues like I am whatsoever. I just finished scanning my PC with Avast! & Spybot, and both say that my system is clean. I literally have no idea why this is happening......

Please help! >.<

By the way I'm on Windows 7 64-bit edition.