AVX offset has been a debatable issue since Kaby Lake. Some said it's a bug while others saying otherwise.
It could be that you have certain OS software running in the background that's using AVX instructions, triggering the AVX offset thingy. Here's the list of AVX-based software: https://forums.anandtech.com/threads/what-c...d-avx2.2498660/
Some games might be using AVX instructions, or NVIDIA driver itself is implementing it: http://www.overclock.net/t/1641867/avx-offset-bug
This doesn't happen with Skylake-X though or he needs more games to test: http://www.overclock.net/t/1643198/coffee-...ks-while-gaming
One guy said this bug is triggered when C-states are enabled in the UEFI: http://forum.gigabyte.us/thread/2704/psa-avx-offset-bug-real
I personally don't use AVX offset because I want my OC to be all out for worst case scenarios. 
Check out the OC guide in the top post of this thread for GIGABYTE's Z370 GAMING 7. It will guide you OCing your 8700K to 5GHz.

But I don't think you can comfortably run 5GHz OC with your current air cooling, unless you hit silicon lottery with a really low VID (stock voltage with everything defaults) and delid. So it really depends on good is your CPU which varies from one chip to another. Get a bigger and better cooler like the NH-D15/S or 240mm+ AIO.

It is advisable to check your VID through the UEFI first before proceeding for OC. Check your CPU core temps with your CPU running at stock clocks with Realbench v2.56, then only proceed for 4.7GHz on all cores and so on.

For record, my 8700K has 1.088v VID and it's capable to do 5.0GHz running under a high-end custom loop at 1.280v on Prime95 v29.3 custom blend 1344K.

I managed to get 5.0 using some guide from internet.
I have attached a pix - your comments highly appreciated.

5.0GHz @ 1.344v seems like an average 8700K, so I think it's not going to run comfortably under air cooling/low end AIO etc.
What's your load temp in your daily applications/games and Cinebench R15?

Do I bring it down lower to say 4.8Ghz?
BTW I am new to Windows having been on Mac all these while
And being new I dont even know much about the temp etc but I have attached another screenshot after running cinebench

Alright guys, currently I am testing my 5.0GHz OC on the Hero X with the an air cooler in the form of Noctua NH-D15S (2x NF-A15 fans).
To my surprise, for some reason I need to pump more voltage as compared to my custom loop.


Noctua NH-D15S: 1.328v, avg core temps: 39C Idle, 86C load
Custom loop: 1.280v, avg core temps: 37C Idle, 72C load

Yes that's right, 0.48v difference! 

At first I couldn't believe it so I re-tested using back my custom loop again I can confirm that there's no chip degradation in which I am still able to obtain stability at 1.280v under custom loop same like before, I don't know why LOL.

interesting. So i might be able to get some voltage down when i pair my cpu with that new corsair 360mm AIO cooler xD.

I understand that the lower temps, the lower the voltage required but seriously did not expect as much as 48mV.. .Funny LOL.
Guess something is not right when the temps go above 80C, don't know...

btw, Corsair H150i Pro RGB 360mm AIO cooler appeared in a recent LTT video. Seems like the launch is not today, but most likely to be released during CES 2018 that will be held in Las Vegas between 7-12/1/2018.

looking forward to it. hopefully it will arrive at our shore soon.

Alright guys, currently I am testing my 5.0GHz OC on the Hero X with the an air cooler in the form of Noctua NH-D15S (2x NF-A15 fans).
To my surprise, for some reason I need to pump more voltage as compared to my custom loop.


Noctua NH-D15S: 1.328v, avg core temps: 39C Idle, 86C load
Custom loop: 1.280v, avg core temps: 37C Idle, 72C load

Yes that's right, 0.48v difference! 

At first I couldn't believe it so I re-tested using back my custom loop again I can confirm that there's no chip degradation in which I am still able to obtain stability at 1.280v under custom loop same like before, I don't know why LOL.

that's quite a huge difference and prolly explains why I also had to pump the voltage that high. for the 72c custom loop, how long did you keep the rig under load?

So this is the result after 2.5 hours priming with the NH-D15S... maximum temp hit 91C

Just went to chevk my bios setting again. Found out my vccio (auto) at 1.336v and voltage agent (auto) at 1.152v . Are these value too high??? My dram voltage it set to 1.35 default.

Those values are almost similar to ASUS's boards running at auto setting.
At DDR4-3200, I have mine defaults at 1.3v and 1.125v respectively but I decided to reduce the VCCIO to down 1.125v and I can still run it stably. As a result, my CPU temp can be reduced a bit. 

Which software are u using to test the ram stability? I have just tune both vccio and vccsa to 1.2v. I am now running prime95 blend test for 2 hrs. Kinda weird, when i click start blend, prime95 stop working msg pop out. but when i try to test again, it is running an hr without any crash. Not sure if the ram is stable or no.
Edit:  After 2 hrs of prime95 blend test, no error or warning or crash. So i guess is stable.

Mine is DDR4 3466Mhz what can I do to tweak it?