Overclocking help for a first timer

[Tuanhphung]

I have an i5 2500k CPU at stock running at 3.3ghz and I want to overclock it to around 4.2ghz as im starting to feel my GFX is being bottlenecked by my CPU when playing games and/or streaming.

I want to know what should be changed in the BIOS menu other than changing the multiplier of the clock speed; Voltage? if so, what voltage would be appropriate at a 4.2 ghz overclock.

Here are my specs below.

CPU: i5 2500k 3.3ghz
RAM: G.Skill 8GB DDR3 1600Mhz RipjawsX CL9 (9-9-9-24) 1.5V
GFX: MSI NVIDIA GTX970
MOBO: Gigabyte GA-P67A-D3-B3 P67 Rev 1.0

Im open to any advice and explanation so I can learn from all this also, Thanks in advance!

 

[Faktion]

Read a Toms Hardware over clocking guide.

Pretty much gives you a step by step with warnings and tips. There are probably 20+ of them posted here. Quick search brought up a ton of them.

http://www.tomshardware.com/reviews/overclocking-guide-part-1,1379.html

http://www.tomshardware.com/reviews/cpu-overclocking-guide,4593.html

 

[Tuanhphung]

Im bumping this thread now as I have finally made the decision to go ahead and try.

I've read multiple guides (including Faktions links) and I have clocked my CPU at 4.2 Ghz. However my voltages are fluctuating from 0.9v to 1.25v, occasionally hitting 1.33v to 1.37v as Max Value, which from what I've read is pretty high for 4.2Ghz overclock.

So I've changed the voltage settings around in the BIOS on the 'Dynamic Vcore' option but HWmonitor are still reading the same values (1.37v at Max).
I've looked in to guides for specifically Gigabyte motherboards where they seem to have 'CPU Vcore' option on their screenshot under voltage settings but mine only has 'Dynamic Vcore' setting. So I'm not really sure if I'm changing the settings under the correct option for voltage.

This is my first time Overclocking, so any guidance is much appreciated.

Thanks