Firefox 3.0 sucks

Like many people I ran out and upgraded to the latest version of the Firefox browser the other day. Now I'm ready to downgrade to the old version. Firefox 3.0 manages to suck up all of my processing power and lock up just trying to open a simple web page (the same pages that version two was opening with no problem last week). I'm willing to give it one more chance if anyone knows of some setting tweaks that can stop it from being such a hog.