Question Overclocking, Why increasing voltage decrease clock speed ?

proropke

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Aug 6, 2014
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Overclocking i5 6600k on Z170A

So it seems that auto voltage doesn't like to go above 1.22v which is only enough for 4.0Ghz, however setting more voltage manually decreases clock speed. I'm completely lost on what is happening.

Temperatures have no affect, CPU fan is running at 5-10% (even on load) when stock and achieves 50C load 25C idle, but for sanity check I did one run with CPU fan always at 100% .

All results below under full load (stress test)

Stock:
clock speed stable (doesn't change) at 3.6Ghz
1.25V/4.2Ghz: clock speed unstable (always different), averages 3.9Ghz
1.36V/4.0Ghz: clock speed unstable, averages 3.4Ghz (below base clock)
1.3V/4.4Ghz/Cpu Fan Always MAX: clock speed unstable, averages 3.7Ghz
Auto Voltage(1.2-1.22V)/4.0Ghz: clock speed stable at 4.0Ghz
Auto Voltage(1.2-1.22V)/4.2Ghz: clock speed unstable, averages 4.0Ghz
Auto Voltage/4.4Ghz: Instant blue screen


TL;DR
1.25V =
3.9Ghz
1.3V = 3.7Ghz
1.36V = 3.4Ghz (below base clock)
 
Last edited:

bryanc723

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There's a happy place between amperage, voltage, and clock speed you have to find. You have not found this happy place. This happy place is very hardware dependent. I don't know intel well enough to know the happy place for your components.
More voltage means more heat and less amperage generally. I dont know which component is failing but the voltage regulator on your mobo might be too stressed.
Are you using a stock cooler? It almost sounds like you're crashing before your system can register to you accurate temps so you're sitting at closer to 80c but only showing 50c, which imo is low even for stock speed, not to mention overclocking.
Perhaps if you could provide full system specs outside of just the mobo and cpu, we could be of more help. Also whatever monitoring software you are using and operating system.
 

proropke

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Aug 6, 2014
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There's a happy place between amperage, voltage, and clock speed you have to find. You have not found this happy place. This happy place is very hardware dependent. I don't know intel well enough to know the happy place for your components.
More voltage means more heat and less amperage generally. I dont know which component is failing but the voltage regulator on your mobo might be too stressed.
Are you using a stock cooler? It almost sounds like you're crashing before your system can register to you accurate temps so you're sitting at closer to 80c but only showing 50c, which imo is low even for stock speed, not to mention overclocking.
Perhaps if you could provide full system specs outside of just the mobo and cpu, we could be of more help. Also whatever monitoring software you are using and operating system.

Fixed everything by increasing CPU current limit (A)
 
Last edited:

proropke

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are you using the stock cooler? and are you adjusting max cache speed to match the OC?

the stock cooler won't keep up with transient spikes in temp. also the cache speed needs to be adjusted (not just voltage & multiplier)
are you using the stock cooler? and are you adjusting max cache speed to match the OC?

the stock cooler won't keep up with transient spikes in temp. also the cache speed needs to be adjusted (not just voltage & multiplier)

Hyper 212 Cooler, I fixed it now though, it was current limit.