lowest price upgrade on mobo cpu ram

hi. it seemed like my old computer (actually it is family computer) decreasing its performance. feel like it. maybe because of my new rig.. still. i want to upgrade mobo, cpu, and ram for lowest price. ive went into the newegg and ive chosen athlon x2 3800. which is less than 50$. im suck at matching mobo, cpu and rams. what the heck the FSB has to do with ram and mobo?? yeah.. so i want some recomendation for mobo. im thinking to get 1g ram. (if you explain about matching those parts ill appriciate it )
im thinking 50bucks for mobo

Are you certain you want to go with AMD?

When overclocking is considered, Intel is considered a better buy, although slightly more expensive.

And it's called Micro atx