When I try to play Call of duty 4, my pings on all the servers jump up to over 1000. But when I can get into a game, the ping is very normal (around 50-100, depending on server location). I am starting to think its something wrong with my computer, beacuse the exact same thing was happening when I was conected to his dsl modem. I tried to forward the ports, but there was nothing. Any ideas?

Suggest you provide us with your computer's hardware.
You can use this link... What's inside my PC? and attached the results page to your reply posting.

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Klaatu Barada Nikto

Check what processes are running that require an active internet connection and kill anything that is not essential. Also it could be worth contacting your ISP to see if there is a problem at their end.

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Ryan M

I've had the same problem, the pings are very high in the server list screen but fine in game. I noticed it only did this when refreshing the list constantly, the first time i viewed the list the pings were fine. Are you refreshing the list frequently?