Question 8700k Core speed is flucuating even at idle. Need help

Feb 29, 2020
First of all sorry for English.

I decided to OC 8700k on Asus maximus x hero board and followed this guide:


plus if you dont trust him i also checked der8auer's guide , its pretty the same (99%)-


Everything is fine (I did not win sillicon loterry cuz i could take 4.8 only with 1.28 LLC6 AVX 1 or 4.9 with 1.32 LLC6 AVX 1 ) , i found my stable base etc etc., the problem is in AVX negative offset.
How it should work (how i understand it) - if pc "face" AVX instruction programms/games/tests it will enable AVX negative offset and will drop -100 (i made AVX 1) to core speed (or will drop core speed to -200 for example if make AVX negative offset 2) - so in stress test with AVX i shoud get 4.9ghz-100=4.8ghz and it works like it should, solid and stable, keeps 4.8ghz while AVX test is going.
BUT the problem is when i test program WITHOUT AVX, core speed is flactuating between 4.8 and 4.9 every seond or two and it doesnt keep 4.9 like it should without AVX in stress. And the most interesting and main thing - EVEN IN IDLE (everything is off, no extra programms running, just clear desktop) it still flactuating and doesnt keep 4.9ghz. I keep getting bouncing core speed from 4.9 to 4.8 (2-4 seconds 4.9ghz, then 1 second of 4.8, then again 4.9ghz).
This happens cuz of AVX, cuz if i make AVX 0 im not having flactuating but systeam becomes not stable with AVX programms and i need up vcore so its not an option ofc cuz i already have pretty awfull results with chip.
ALso i know that it not should work like that cuz if you will look at this time code - 15:04


or this time code from der8auer guide - 10:02


Their core speed is stable with Ghz they set (5000 for example) and AVX starts working ONLY when AVX programm is running (test).

Some old forums say that it maybe happens cuz "windows 10 using AVX too", yeah it could be but why those guys from guides (+ many users from everywhere) have it working like it should with the same motherboards.

Bios version - last one, Before setup OC made CMOD + stock settings reset + bios update. After that 100% followed guide from 1st video (but i tested de8auer's settings too)
In win10 set Maximum perfomance.

Need someone who can explain whats wrong and how to fix those flactuatings with AVX in idle

Asus maximus X hero (wi-fi ac)
G.skill tridentz RGB 3200 4x8 cl14
Seasonic prime 850wtt
Last edited:
you might also be hitting TDP/power limits of 95 Watts...; those (and time under max turbo) would easily need to be removed to maintain peak turbo speeds indefinitely, assuming no mainboard VRM threshold temps are exceeded...