dear all sifus.

say if i want to OC my pc can i just change the multipler only? and not increase the voltage.

sure can, but if your chip need more juice, you still need to increase the voltage. btw, try use existing thread in this forum. according to your siggy, try seek the solution here >http://forum.lowyat.net/topic/1143995

how can i overclocking ? just change my uefi setup to 3.8ghz,4.0ghz.that means i already overclocked ?

if your original CPU clock is 3.5GHz, means you had overclocked about 10% (assumption only). so far i know overclocking can be done at your mobo BIOS by the same method, increasing the multiplier and core voltage.

my processor is core i5 3.4ghz.. current running 3.8ghz on my extrem4 mobo.. so the voltage and everthing is ok ? sorry im new to oc also.. i just changed the core speed on the mobo uefi setup only..

well im not an overclocker but if you experience no crashes in windows boot up, means you are ok. if crashes exist, you have to adjust the settings.