overclocking fsb (front side bus) will overclock a few things at the same time, cpu, ram, and northbridge. That being said its easier to just up the multiplier to oc the cpu and leave the fsb alone.
To oc your cpu properly ( this will take a long time cause of testing) start by going into your bios (delete button when starting computer. Just bring up the multiplier by 0.5 and save and reboot the computer. open a temp monitor like hwmonitor, and open prime95. start p95 and watch temps (dont go above whatever the max temp is for your cpu). run p95 for a couple of hours, if one of the workers stops working the system is unstable and you need to add voltag, DO NOT ADD A WHOLE BUNCH OF VOLTAGE AT ONE TIME, go up by small increments, problably the smallest your mobo can handle. then repeat p95 untill stable. Once stable you can do it all over again, add multi by 0.5, test, if unstalbe add cpu volt, test, etc.
Now just cause i can never say this enough WATCH YOU TEMPS. To much temp can kill you cpu really quick, so its problably best not to oc if you dont have a decent cpu cooler.
Oh ya and just to make myself clear agan WATCH TEMPS, never go over the max temp your cpu can handle.