i5 7600k Overclocking Questions

[dcolby10]

I've been looking into overclocking my Cpu and I have come across some questions that I can't find definitive answers to on Google. Little background on my system first:
Cpu: i5 7600k
Mobo: Msi Z270 Sli plus
Current cooler: hyper 212 Evo, but I'll be putting a DH-15 on this afternoon.

I am shooting for 4.5 - 4.6 GHz, is that gain worth it over the 4.2GHz boost clock that the 7600k achieves? I mostly play Wow and Overwatch with a 144Hz 1080p monitor, so rather cpu bound games. But is a 400MHz overclock even worth the hassle?

If so, what is the best vcore method to use? Some people swear by the manual method, but that forces constant voltage even when idle. So is adaptive the best? Also when using adaptive vcore, is Llc required?

Last night I decided to push the core multiplier up to 4.5ghz just to see if the hyper 212 could handle it. I set the vcore to adaptive and put the max at 1.15volts. I then did a simple 5 min stress test in XTU. CPU-z said that the vcore was 1.16v or so and the system passed. But when I ran the XTU benchmark, vcore went up to 1.20v. Is that a side effect of adaptive vcore, or is that LLC coming into play?

 

[rodolphe.viard]

Hi dcolby10,

First i'll answer your question then explain overclocking :

The 4.2GHz Boost is when 1 core is loaded. When all cores are loaded, your actual boost is 4GHz.
So 4.5-4.6Ghz on all cores gives you between (4.5-4)/4=12.5% and (4.6-4)/4)15% frequency boost which give around 10% Performance gain, non negligible.
Adaptative will let your voltage fluctuate with the load so that's normal to see a little difference between different stess test software.


You're doing overclocking the wrong way.

The first Goal of overclocking is to find the minimum voltage required for a given frequency
First, at stock, note your frequency and voltage you can read during stress test.
You put them in manual mode in your bios.
Then, you have two ways :

1°/ Better performance :
With stock voltage, bump your multiplier until it's not stable then bump voltage (increments of 0.025-0.05V) and so on.
Once you've reach the stable frequency you want, lower the voltage as much as you can as long as it remains stable.

2°/ Better thermals :
Keep stock frequency and reduce voltage as much as you can until it's not stable.

For 1°/ and 2°/, once you're done with your tweaking and that everything is stable for your usage, you can re-enable power saving features as C-States and put the voltage on adaptative to let the voltage and frequency fluactuate with the load.

Tips: stay below 1.38V and 85°C during stress test for daily usage.


Rodolphe.

 

[dcolby10]

Hi Rodolphe,

Thank you for your reply and insight. I will definitely be overclocking now as it is clearly worth the time and effort. I installed my NH-D15 last night so thermals should not be an issue with a minor overclock.

So at stock in the realbench stress test, CPU-z states 4200MHz and 1.19V - 1.20V. So following your procedure, I would raise my multiplier with the voltage overridden to 1.19V and stress test? Then start lowering the voltage in small increments right? I know that every chip is different and silicone lottery and such, but I have read that many 7600k's are stable at 4600MHz and 1.15V.

I attempted to overclock last night but I was having issues with the vcore not matching the overridden value in the bios. I had it set to 1.15V in the bios but it would be running at 1.168V - 1.177V in the stress test. I read that LLC could help, but none of the settings seemed to keep the vcore at the value I set it at. This was with vcore in manual/override.

Again, thank you for your help!

 

[rodolphe.viard]

That's normal if the voltage is not exactly what you've put in bios. LLC feature is here for that.

LLC compensate for the voltage loss due to the load.
Perhaps try a lower level. With your Mobo (i've the same but with z370 chipset) try llc level 4.

"So following your procedure, I would raise my multiplier with the voltage overridden to 1.19V and stress test?" Exactly, until it's not stable then rise the voltage and redo the procedure.

Just keep in mind that overclocking is a game of trial and error.



Rodolphe.

 

[Signature818]

Hi dcolby10,

First i'll answer your question then explain overclocking :

The 4.2GHz Boost is when 1 core is loaded. When all cores are loaded, your actual boost is 4GHz.
So 4.5-4.6Ghz on all cores gives you between (4.5-4)/4=12.5% and (4.6-4)/4)15% frequency boost which give around 10% Performance gain, non negligible.
Adaptative will let your voltage fluctuate with the load so that's normal to see a little difference between different stess test software.


You're doing overclocking the wrong way.

The first Goal of overclocking is to find the minimum voltage required for a given frequency
First, at stock, note your frequency and voltage you can read during stress test.
You put them in manual mode in your bios.
Then, you have two ways :

1°/ Better performance :
With stock voltage, bump your multiplier until it's not stable then bump voltage (increments of 0.025-0.05V) and so on.
Once you've reach the stable frequency you want, lower the voltage as much as you can as long as it remains stable.

2°/ Better thermals :
Keep stock frequency and reduce voltage as much as you can until it's not stable.

For 1°/ and 2°/, once you're done with your tweaking and that everything is stable for your usage, you can re-enable power saving features as C-States and put the voltage on adaptative to let the voltage and frequency fluactuate with the load.

Tips: stay below 1.38V and 85°C during stress test for daily usage.


Rodolphe.

Nicely done!