There's the key: "uTorrent works fine, but browsing and using download helpers don't work after a while."
Your pirating of music/software/movies is your problem. Of course since what you're doing is almost certainly illegal, you're on your own to figure out the why. I'll just say that if you stopped pirating goods, your Internet connection should remain pretty stable more or less indefinitely.
I just recently bought a Lenovo Ideapad Y450 straight from Lenovo. It came with Vista Home Premium 64-Bit. I installed the the usual: AVG, Zonealarm, and a few other things. Now, wifi gets slower the more I do browsing, and eventually pages don't load and the browsers - IE, Firefox, AND Chrome - say that I don't have wifi, even though I have as high a wifi strength as it can go, which is 5 bars. The only way I have fixed this is by restarting the machine, which takes a while, and it tiresome just to get internet. uTorrent works fine, but browsing and using download helpers don't work after a while.
I searched and found that AVG doesn't like Vista, so I turned off the browser stuff, and then it started working again, but now it's doing the same thing it did before.
I need solid wifi for college this fall, and I DON'T want to return this laptop for another one - my budget just can't take that.

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