1. [Optional]Try this: Restart comp. (To reduce the amount of connections your computer have.)
2. Then "start->run->cmd->netstat-n"
3. Then see what addresses you can see.
4. Then Go to the website and do "start->run->cmd->netstat-n". Then see if there's a new IP. You might see the port there.
PS Haven't tried with webpages. Only games.