in general terms,over clocking is for CPU. your CPU is safe to run at 2.0 GHZ. overclocking means running more than intended speed. biggest ememy of cpu is heat, and overclocking means generating more heat. your current cooling system might be not sufficent to handle extra heat. that might result in death of processor if your overclock extremely.(you lose your warranty for overclocked deadth cpu)
overclocking is trail and error process. you may start with small increment in speed. see the system stability,then continue to next increment.but don't go beyond 2.1 ghz without propercooling.in now way you should rushs for greater speed.
if you are not gamer or doing Rendering work, stay away from overclocking.
you will not notice any major performance improvement in general use. same is for RAM tweaking in bios.