Pc freezes on stock settings after overclocking

[morluka]

Hey, first of all, my build:
Asrock z370 extreme4
I5 8600k
Corsair vengeance 3000mhz 2x8gb
Gtx 1080 Gainward Phoenix
SilentiumPC supremo m2 gold

So i was overclocking to 4.8ghz @1.25 voltage, ran p95 for about 15 hours, no errors, everything fine. I have been using this setting for around 1 week and i decided to lower the voltage a bit. After l lowered it i encountered the first BSOD when tried to launch CPUZ. I raised the voltage a bit but on PC restart, when loading up to Windows PC froze, no BSOD, i was forced to hard restart. After the restart, everything lunched up smoothly, then i was playing casualy some non-CPU stressing games (League of legends) And after about 1 hour PC froze again, no BSOD just looped sound. Was forced to hard restart again. I raised my voltage but it happened again, then again and again. I tried fixed voltage, offset voltage but it kept on freezing after 30mins - 2hours. I decided to run stock CPU settings with xmp profile loaded. After 2 hours it froze on stock.
What should be my next step?
Thanks in advance

 

[vMax]

Have you tried the LLC setting to a bit higher as this does look like a vdroop issues...

 

[morluka]

Yes I was trying to use lvl 1 and all other possible levels, still freezing on stock. Im in the middle of a memtest right now, 38% passed no errors so far

 

[vMax]

Okay fingers crossed. I can do 4.9GHz at 1.278v with a high LLC setting...My motherboard is a Gigabyte and has a slightly different LLC setup...from normal, high, turbo and extreme..

 

[morluka]

Passed memtest 3 times with 5:30 h, no errors. PC still freezing at stock, I really dont know what to do.. . I used to run 4.8ghz @ 1.25v stable. Should i RMA?

 

[vMax]

Passed memtest 3 times with 5:30 h, no errors. PC still freezing at stock, I really dont know what to do.. . I used to run 4.8ghz @ 1.25v stable. Should i RMA?

I cannot think it is an issue with the CPU...I think if you can reset the BIOS by clearing the CMOS and starting again with the first good 4.8GHz setup you had at 1.265v and the memory on XMP just to test...then bring it down if all is okay...

Also what CPU cooler are you using?

Try that first...

 

[morluka]

I will try. The cooler is SilentiumPC grandis 2, its a polish brand offering good value for money

 

[vMax]

I will try. The cooler is SilentiumPC grandis 2, its a polish brand offering good value for money

I see...It would be great if you could do a Prime95 version 26.6 blend test run and see what temps you reach...

 

[morluka]

Cleared CMOS, PC froze after 3h of playing

 

[morluka]

Any suggestions?