i5-6600k keeps crashing

[daslopf]

Hello,

i have tried to overclock my CPU after 18 months of usage for the first time.
Im mostly playing CPU heavy FPS Shooter like CPU PUBG and R6. The CPU is having 100% usage and it costs me the stable fps for competetive play.
Yes its my first overclock and i informed myself about risks and the procedure itself. I listed all components below.
First of all i tried the pre set settings with 4.2 and 4.4 GHz but this lead to high temperatures 75-85°.
After this i tried to use a 42 and 44 multiplier. The temperatures were fine ~65°. I tried the following voltage for each multilplier 1.25/1.275/1.3.
I used Intel extreme tuning stress test for 30 minutes for each setting and had absolutely no problems while spectating CPU-Z and HWMonitor. I even played several games and rounds but the blue screen only appears when i close all application and im on desktop.
I also tried XMP Profile on and off.
What am i doing wrong?

Intel Core i5-6600k
ASRock Z170 Gaming K4
Gainward GeForce GTX 1070 8GB
Patriot Memory Viper Elite Series DDR4 16GB 2400 MHZ RAM
Corsair RM650X 650W
EKL Alpenföhn Brocken 2 PCGH-Edition
be quiet! Pure Wings 2 140x140x25mm 1000 U/min 18 dB(A)

 

[zyh1987]

Set load line calibration to medium or the middle ( I forgot if it’s a number system or not) setting should improve system stability at high cpu load.

 

[daslopf]

Set load line calibration to medium or the middle ( I forgot if it’s a number system or not) setting should improve system stability at high cpu load.

Okay, i checked LLC. I am able to choose between Off / Level 1 / Level 2 / Level 3 / Level 4

I switched to level 1 but it still crashed. I cant understand why its not stable.

 

[zyh1987]

Try bump up your core voltage by 1 increment. Also llc should show you a graph explaining I think lvl1 is flat and lvl4 is sloped, you want to have 2 or 3. Here is the great guide by Der8auer, even though it’s a Asus board, you can draw similarities in asrock board.
https://youtu.be/gMWCFwKBQtQ

 

[daslopf]

So: I followed the video guide. I increased my Vcore to 1.28 and a 44x. I set XMP to Profile 1 and LLC to Level 2.
I run Intel extrem test for an hour and it was fine. No temps above 68. I had no bluescreens after gaming anymore.
After this i tried Prime95 as shown in the Video. And then all the troubles begins:
Prime 95 is not working on all cores after one minute. When i start the small FFT only 2 out of 4 Cores are working (i guess, because only 2 temps are going up ~80 and the other two are at ~40).
Whats the matter here? Any help?

 

[zyh1987]

Prime 95 test, Did it crash or just not stress all four cores.

Also in power option set it to performance mode.

 

[urbancamper]

Use prime95 version 26.6. You can find it on this page. Anything above that version also tests AVX instructions, which basically are used in scientific research type stuff. It will not only put a crazy amount of heat on your cpu, but can also cause instability.

Yes 2 of the cores did crash. I think you need to raise the vcore a little more. Try 1.3 or 1.31v. When I had my i5 6600k@4.5ghz my vcore was at 1.328v. https://valid.x86.fr/l5z6hl