Fast download speed - slow browser speed-slow& d/c duringTF2

[Beetle]

So over the past week I have had internet problems. I noticed myself getting randomly disconnected from WoW, starting off every other day now up to the point where its every other minute. If I try to play TF2 or L4D (for example) it connects me then disconnects me within 3minutes. I checked the cables, called my ISP, checked drivers, even last night I reformatted and started from scratch and its still crappy. I tried the wireless adapter I have on my computer (on-board just like my ethernet adapter) and its the same. We replaced the router with a brand new one, still sucky. My friend who shares the connection has fast browsing speed as if nothing changed.

I am thinking possibly some hardware in my computer got damaged, maybe overheated? Anyone have any ideas? This is killing me. I can't do anything cept download things at a good pace, everything else isn't worth doing.