Crashes browser after some time?

[armanur]

Hey guys, I'm having some really serious problems with my laptop. All of a sudden, all my browsers (IE 8, FF5, Aurora, Chrome) are lazy to do their work. Maybe a virus or something in the network? The laptop is like 3 years old, latest Win XP - genuine, Eset Smart Security 5 RC - installed after the problems started occuring, IMF - a long time ago, latest drivers on everything... I don't recall of installing or doing something "wrong" when the problems started... The problem is that everytime I turn on the laptop, everything works like a charm, I browse the internet, forums, gamesites, facebook, youtube... but suddenly I try to open a site (anything, like just google.com), or when a site is loading, browser freezes, you can't do anything just close the tabs... But the processes (iexplore, chrome.exe, firefox.exe) are still running, with constant memory sipping and increasing PF - nothing big, after 20 minutes just like 500,000 ... you cant kill the process even with pskill... firefox isn't running til a restart, chrome is running for a few minutes after opening a new instance of it... But now the problems are even worse, I had the computer turned on for some hours and when I opened chrome, there was an error like something with proxy - I don't use proxy, I'm wireless connected to a router which is working without a glitch for a LONG time... you can ping anything, play games over internet, download anything, but browsers just won't work... Tried to reinstall chrome, didn't work... completed many malware/virus scans, nothing found... What can cause the problem? Thanks in advance guys, it's crucial