i have overclocked every CPU I have ever owned, and i have NEVER had one fail. It really depends how far you are pushing it (particularly when increasing voltage) and how cool you keep it. A phenom 955 needs to be kept really cool to be stable, and around 3.8ghz it a good place to aim for overclocking without having to pump up the voltage too much. So you will need to buy a good cooler. If I were you I would go for an intel setup, core i3 or i5 2xxx chip and motherboard. Even if you dont get the more expensive K series cpu for overclocking, it will still be as fast or faster than an OC'd phenom 955 in most games (assuming your building a gaming PC) and you have much better upgrade options for the future. I really dont see the point in considering an AMD setup knowing that the upgrade options are very limited when for the same price you can get an equivelant Intel SB setup. When they run out of Phenoms, your only choice will be an FX chip, which are unfortunately slower than the phenoms.