Question Overclocking an i7-8700K with an AORUS Z390 Master mainboard

[thegreek87]

Hi there,
I recently purchased the Aorus z390 mainboard to overclock my i7 8700K. My previous mainboard was an ASUS Prime z370-P, not realy a good choice to run an overclocked system.
Tomorrow i will install the mainboard in to the chase.
I want to run the System daily at 5GHz, because im using Prepar3d with a lot of Addons and it only runs smoothly in an overclocked condition.
I've searched the web for tuturials, but i didnt found something related to my system, only for the Intel 9th Gen CPUs and im afraid, that i will "kill" my CPU if i use one of these guides.

As i mentioned, i have a i7 8700K (delidded)
My powersupply is a be quiet! Dark power 11 650W 80+ Platin. I think that is enough.
Mainboard will be the AORUS Z390 Master
Graphics: RTX 2060 (6GB)
DDR: 16Gb DDR4 RAM (Freq: 1500MHz)

It would be very helpfull, if somebody could list up the settings, which i have to make in the BIOS

I'm asking for help, because i know inly the basics of overclocking and i dont want to mess up my CPU, Mainboard etc.

If you need any other info just tell me!

Thank you for reading and hopefully for your help!

 

[Darkbreeze]

This should be all you need for specifics on overclocking 8th Gen Coffee lake CPUs.

https://www.tweaktown.com/guides/8481/coffee-lake-overclocking-guide/index.html


And this should give you plenty of basics to help ensure you don't screw up by not following best practices when configuring and testing your overclock.

CPU overclocking guide and tutorial for beginners

Covering the basics If you found your way here it's likely you are looking for help with basic overclocking. Either that or you're a long time overclocker interested in seeing whether I had any eye opening insights that you may have been lacking. Rest assured, I don't. This is only intended as...

forums.tomshardware.com

 

[thegreek87]

Thank you for your answer Darkbreeze, but i cant get it stable!
I set to 5GHz and started from 1.3V untill i reached 1.37V and i fail everytime the Prime95 test
I've now got down to 4.9GHz started with 1.3V and now 1.31V and still fail the Prime95 test!
The LLC is set to Turbo.
It happend also to restart at idle from its self with the eventID 41 cat: 63
My powersupply is very good and i also pushed the OC Key on the be quiet! powersupply!
I've plugged in to the CPU Power supply pins all the 12 Pin, so 2x 8pins, on the motherboard, i dont know if this has something to do with it, i thought it would destress the Board and the CPU.

There are only guides with the i9 9XXX and no with the i7 8700K, so i cant find something related to my system!


I dont know what is going wrong. I've spend so much money and it wont work smoothly as i imagined!

 

[thegreek87]

I Think i've found a solution.
I set the AVX to 3 and disabled the turbo mode. I've also changed the the voltage long and short duration to its maximum.
Then I started by 5ghz and 1.31V
Now Prime95 is working for about 20 min without any failure.
CPU temps are about 86° Δtemp-max
The core speed is at 4.7ghz because of the avx.
When its stable for 30 min I will try to deactivate the avx and I will look then if it will be stable at about 1.33V

 

[thegreek87]

Update:
Without AVX I dont pass the prime test at any core volt. settings.
But I stabilizet the corefreq at 5GHz and AVX at 1 with 1.33v. Max temp ist about 90°.
I just passed the 36K self-test of prime95. I think that are satisfied results.
I just wanna see if I can find tune this settings at 1.325V

 

[Darkbreeze]

Not every chip CAN be stable at 5Ghz. I'd suggest what you want to do is start over at about 4.5Ghz, and work your way up.

If you reach a plateau at 4.7Ghz, then it is what it is. If it's 4.9Ghz, then that's the peak for your chip. There's a reason it's called the Silicon lottery..

90°C is TOO hot. 81°C is TOO hot. If you can't maintain a thermal maximum of 80°C or less, running Prime95 version 29.6 build 6 with AVX and AVX2 disabled, then as I've said in my guide it is MOST likely that you either have a chip not capable of the clock frequency you are testing at, or you lack sufficient cooling whether due to a CPU cooler that isn't up to the job or a lack of enough case airflow, or you have too much core voltage.

If cooling is adequate and you cannot reduce the core voltage without introducing instability, then your chip is simply not capable of that OC. It's always possible there are other factors involved as well, since there are a great many ways to affect an overclock such as a motherboard that isn't good enough to maintain the stable power delivery necessary, or you're running too many DIMMs or DIMMs which are too fast with too much overall voltage which is influencing the CPU negatively or some other detail exists that might be tweaked. Generally though, you don't try to start at 5Ghz. You start at a lower clock speed and work your way up.

Also, that is only in regard to the thermal aspect. There is of course still extensive STABILITY testing to be done and I suspect that if you run Realbench you'll find instability exists which means you need to add core voltage except you can't, because you are already beyond the point where thermal compliance is already not acceptable.

 

[thegreek87]

Hello Darkbreeze and thank you for your answer!
I think the system runs now stable at 5GHz and with AVX enebled at 1 (4.9GHz).
But when i have some time, i will try to disable AVX and start at 4.5 GHz to see how far i can get!

After work, I will attach 4 pics from cinebench 15 and 20. One will be during the test and one when its finished.

Thank you very much!!