Welcome to the forum Summerschool.
Unfortunely that is about all the help I can give you for that is a very weird thing to happen. My only guess which is probably pretty far off, is that, you have running processes in the background of your computer and somehow after its been on for a while, increase the CPU usage, hogs up more memory and in turn causes the computers internet to lag. But that is my only guess, i think, we need Van for this one.
i agree, this must be a problem with memory or CPU usage
try cacheman XP
http://www.majorgeeks.com/download4102.htmlVanBuren
