Problems with i5 6600k overclocking

[Janis Bergis]

Hello.
I have a problem with overclocking my 6600k.
So i have set multiplier to 45 and it runs on 4.5Ghz and my vcore on 1.35V but when i start to stress test it my voltage sometimes drops to 1.296V and frequency to 3,8Ghz.
Here is a video of my problem: https://youtu.be/SYTGhMf6MXk
What could be the cause of this?

Specs

MB: Msi z170a gaming pro
CPU: i5 6600k
Cooler: corsair H100i GTX
Psu: evga 550GS
Ram: 8gb hyperx
Gpu: Asus gtx 970

 

[Barty1884]

You likely have C states enabled (or 'adaptive') in your BIOS. Essentially it's maintaining the power-saving features so will reduce voltage & multiplier as needs (much like 'stock' to 'boost' as standard).

You can disable C states or similar if you really wanted your CPU to run at 100% 24/7 - although the power saving features do come in handy. Sorry I haven't OC'd on an MSI board to know exactly what the settings are called.

I'm not sure why voltages & speeds would drop while stress testing, that's exactly when you'd expect them to 'ramp up'.

Try disabling the C states & any 'adaptive' or 'auto' settings for CPU clock - and see how what happens when you stress test then.