First Build Overclocking Help

[rundaddy12]

Hey guys. I just built my first system and I need some help overclocking the cpu.

I have:

CPU: i5 2500k
MB: Asrock z77 Pro4
http://www.newegg.com/Product/Product.aspx?Item=N82E16813157296

I can change the bclk and the multiplier but I cant (or at least I cant find it) change the vcore. Their are lots of voltage options but non for the vcore. Could this be because I have a certain box disabled that should be enabled or something like this? any help would be awesome. Thanks.

 

[DJDeCiBeL]

From looking at the manual, it looks like it should be called "CPU Voltage" in the voltage section of OC Tweaker.