Catalin

Junior Member
Feb 21, 2017
16
0
36
Hello. So, i've upgraded my pc to the next configuration: cpu i7 6700k + cooler Scythe Ninja 4, Asrock z170 pro4s motherboard, gpu card gtx 1070 and 16gb ddr4. I started to OC my cpu to see if i can make it stable at 4.5ghz, because that's the point where i want to keep it. I stabilized it at 4.5ghz(45x100mhz), all core option in bios, at 1.32V and LLC Level 3 (on Level 1&2 it wasn't stable, got blue screen for each). On idle when i turn on my pc, on cpu-z the voltage shows up 1.312V(even though on bios it's Core Voltage Manual set: 1.32V), and because of the LLC Level 3, in stress test with prime95 and aida64, after 10 minutes each, it was stable, but the voltage was 1.280V(with LLC Level 1 1.248V and with LLC Level 2 1.264V), temperatures were pretty fine, 75 celsius degrees in stress. Everything was good, but after 1 hour since i ran the tests, when i was in desktop just doing some ordinary things, nothing to use the cpu even at 10%, i got a blue screen and restart. I said, ok, let's get down to 4.4ghz( i didn't wanted to raise the voltage to see if it will be stable), i set the voltage to 1.30V same LLC Level 3 (again with Level 2 and 1 it didn't worked, blue screen), and again it passed the stress tests, and, after 30 minutes, same thing in normal desktop, blue screen. I set it after to 4.3ghz at 1.28V Level 3 LLC, and for 3 days it was stable, no errors.
I want you to ask if it's possible to stabilize it at 4.5, what other things should i try? I have a friend with a better mobo, an Asus Maximus VIII Impact, and with MY CPU, it was stable at 4.5 @ 1.25V. So, it's because of my mobo? Is it capable only for 4.3ghz? If you have more questions, i am here to respond you all, thanks.
 

Majcric

Golden Member
May 3, 2011
1,369
37
91
Raise the LLC another level or 2 to help offset the voltage drop. It's fine to come up some more in voltage. Just be sure to keep an eye on temps.

Motherboards can make a difference I seem to get the best OC out of ASUS.
 

Catalin

Junior Member
Feb 21, 2017
16
0
36
I tried all LLC levels, i only have auto, 1,2 and 3. On 1 and 2 i get blue screens in stress tests, and on 3 i only got blue screen when idle. I didn't tried auto. I raised my voltage to 1.35 now and still level 3, so far so good, after 5 minutes of prime max temp of a core 78, min 75. I will see if this holds up and no blue screen, it might work out, right? I guess it's decent. Even though in gaming it won't heat up so much.
 

Majcric

Golden Member
May 3, 2011
1,369
37
91
Yes hopefully it will work out. And you're right gaming temps will never be that high.
 

IEC

Elite Member
Super Moderator
Jun 10, 2004
14,328
4,913
136
You will probably need to raise voltage to get stability.

I have trouble hitting stability beyond 4.5GHz on my 6700K even with 1.4V... just a poor OCing chip in my case.
 

IEC

Elite Member
Super Moderator
Jun 10, 2004
14,328
4,913
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It totally depends on your chip, and will require testing. If you get stability at 1.35V you can try reducing to 1.34V or similar and see if it remains stable.

The goal is to use the minimum voltage necessary to achieve your desired overclock. And every chip will be different.
 

LTC8K6

Lifer
Mar 10, 2004
28,520
1,575
126
IIRC, you should not set the voltage to manual, because it will always be at that voltage, even at idle. Rather use a + offset, so that the voltage still comes down at idle?
 

Lepton87

Platinum Member
Jul 28, 2009
2,544
9
81
So with a high LLC your CPU is stable at load and hangs up at idle? Turn down your LLC and raise the voltage by the amount you lose at load from lowering LLC so you have the same effective Vcore at load. That way you should be stable at both idle and at load.

ps. Does it even make sense to OC that CPU at all? You gain 7% more frequency over all core turbo but you probably more than double the power consumption.
 

Catalin

Junior Member
Feb 21, 2017
16
0
36
Well, I've raised the voltage from 1.32V to 1.35V, same LLC Level 3, and after prime&aida stress cpu test, all was good. My max temperature was 80 celsius degrees at 1 core, and 77 celsius degrees on the rest. I also played for 1 hour a game, and max temp was 72 celsius degrees. No blue screen by now.I guess it's ok, right?