I heard people said that it's posible to overclock the Pentium G3258 with stock cooler. Is that true? If yes,how many ghz can I overclock it to? and is there any website for overclocking guide for this processor ?
I dont recommend OCing any processor on its stock cooler, the cooler is designed for stock speeds.
Pick up something like the 212 EVO, or larger, to OC that processor with.
Sure, I got mine oc'ed to 4.4 GHz on stock cooler @1.28 run pretty fine temps are around 80 's at full load and 60's wwhile gaming. PS runing on a MSI b85g43 gaming. So a cheap and non Z mobo can get a nice overclock.