I don't overclock as theres too many things that can go wrong. The performance increase in my opinion at least is pretty poor considering you are risking your machine blowing up. I appreciate you can take it a bit at a time to lessen any risk but considering you have a dual core 3800 I have to ask what the point is?
I'm sure others will completely disagree with me on this and I'm sure theres quite a few members on this Forum that do overclock but I'm not one of them. I also think you'd get more advice on a dedicated overclocking site but good luck in any case.