Internet Connection dropping after playing online games?!?!?

[Razielim423]

Hello everybody.

Specs
Windows 7 ultimate
AMD Phenom II x4 975
8 gigs of ram
Radeon HD 6870
Motorola Router model # sbg6580 Wired connection

My computer has started acting really weird. My internet connection is fine except when I try to play a game online I'll be on for a few seconds and then the connection shuts down. Not just for the game but for everything. When I used windows troubleshoot it had these errors.

"the connection between your access point router or cable modem and the internet is broken default gateway is not available: detected" and

"the default gateway is not available:fixed"

After I do that I have a connection again but the same thing happens when I play another game.

I have tried updating my drivers, scanning for malware of all sorts, registry cleaning, and I even reformatted. I did eventually come across something that helped a little http://hardforum.com/showthread.php?t=1455243 I followed those intructions but it seems to have just bought me a little time before my connection dies on me again.

I have no idea what else to do, any help would be very much appreciated. I'm at my wits end.

 

[Razielim423]

I should also add that no one else in my household is having this problem and a few play games a lot.