D-Link DIR-655 :: Stopped Working For Some Games?

I've had the dir655 for about a year now, and no problems at all, until about a week ago. I went into a couple of online games (Bad Company 2 and World of Tanks) and would have a low ping showing in the game, but every 10-15 seconds, especially in areas with a lot of action, I would get large amounts of lag, making the games unplayable.I would be unable to move or keep getting 'teleported' back 20 feet. I looked into it maybe being the servers, steam in the case of bad company, or my internet provider, but regular internet actions are not affected at all. After searching for a while tweaking settings, turning off antivirus and firewalls, it made no difference.I finally today plugged my modem directly into my pc instead of leaving it on wireless, and all the problems go away. All packet tests and connection tests to my router have come back with no errors. Again, I have never had a problem just browsing the web or watching videos, and usually get more speed on speedtest.net than my provider even advertises. I also upgraded the router firmware.I tried going into my router settings and doing all I could (as I understand it) to have exceptions, port forward, and even did the one thing (can't remember what it's called) where you add one ip address that will have no limitations put on it by the router, and none of this has made it work.