Ok here goes....
The problem usually occurs when I am watching streaming videos through an internet explorer or Opera. It does not matter whether it is youtube, crunchy roll, etc. The streaming videos would just stop halfway or not load at all.
The other problem is when I am downloading files from the internet. It happens to any site I choose to download the files. I tried download.com, divx.com, openoffice.org, any site would cause a problem. Surprisingly, the problem does not occur when I downloading stuff from a bittorrent application or receiving files from Msn messenger.