What is this FF everyone speaks of? I see a discussion about Firefox, and then FF. http://www.mozilla.com/en-US/firefox/releases/1.0.6.html#FAQ It sounds like an extension problem. Try running Firefox in safe mode "C:\Program Files\Mozilla Firefox\firefox.exe" -safe-mode How many tabs are you using? I saw it was asked but never answered. Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9b5) Gecko/2008032620 Firefox/3.0b5 - Build ID: 2008032620 - 36 tabs @ 77,500 K mem usage reported by Task Manager.