[SOLVED] "Stable" OC with way lower vcore than Silicon Lottery suggested?

_dawn_chorus_

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I am an OC newb with a delidded 8700k I got through Silicon Lottery, they binned it as stable at 5.1Ghz at 1.412 vcore with -2avx offset. That of course got insanely hot..
So I have sort of started backwards and have moved down to a 5Ghz 1.35 vcore and -1avx offset LLC at medium. So far it has made it through an hour of realbench stress test, an hour of prime95 small FFT avx disabled, and another hour of prime95 blend test, so it is looking pretty stable so far but have yet to do a multi hour run. Stays in low to mid 80's spikes to high 80's.

My main question is how can I have a vcore so much lower than what was recommended by Silicon Lottery with my clock speed only 100mhz less? Does that extra 100mhz really require an entire .6v to be stable?
I feel like I am missing something here because they must be experts but my vcore is so much lower and seems to be stable.
Below are pics of my settings so far. Any other thoughts? Suggestions? What might I be over looking?

8700k dellided
NH-D15
z390 Aorus Pro
32Gb Corsair Vengeance 3600 c16
CorsairRm850x

View: https://imgur.com/a/gGWnV7E
 
Solution
If you are using offsets, then that might change things a bit, if you are testing with no offsets but plan to use offsets after testing because obviously the use of AVX in games or applications would then not be likely to reach the same thermal peak as with it enabled.

For the purpose of longevity alone, I would certainly never allow a daily driver to be overclocked to a level where it is seeing, at most, 85°C. If you look at the data in the intel temperature guide you'll find that due to thermal degradation and VT shift it specifically says this:

If your hottest Core is near its specified Tj Max Throttle temperature, then your CPU is already too hot. The consensus among well informed and highly experienced reviewers, system...

Lutfij

Titan
Moderator
The thing about overclocking is trying to find a balance with what you want out of the platform/part and what you intend to task it with 24/7 and if the risk/reward is worth it. As you've found out, getting that extra 100MHz requires much more power than you would've needed if you were on lower clocks, that's the point of diminished returns for your particular chip. In fact last I recall, you should try and stay below 1.3v if you intend to retain the chip for a long period of time.

Heat does rob the processor and the platform of crucial performance which is tamed with a good air/watercooler but what most people neglect to mention is that pushing high voltages through your processor/board/ram degrades the internal construct of said part and then it's the point of no return.

Can you dial it down a little with volts but reduce the memory frequency to 3200MHz? If you're chasing behind a record run, then you're fine, if it's for a build that's meant to be a daily driver, then you should dial things down for longevity.
 

_dawn_chorus_

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The thing about overclocking is trying to find a balance with what you want out of the platform/part and what you intend to task it with 24/7 and if the risk/reward is worth it. As you've found out, getting that extra 100MHz requires much more power than you would've needed if you were on lower clocks, that's the point of diminished returns for your particular chip. In fact last I recall, you should try and stay below 1.3v if you intend to retain the chip for a long period of time.

Heat does rob the processor and the platform of crucial performance which is tamed with a good air/watercooler but what most people neglect to mention is that pushing high voltages through your processor/board/ram degrades the internal construct of said part and then it's the point of no return.

Can you dial it down a little with volts but reduce the memory frequency to 3200MHz? If you're chasing behind a record run, then you're fine, if it's for a build that's meant to be a daily driver, then you should dial things down for longevity.

-NOOOOO hahaha... Why would I lower the ram speed? Does that ease stress on the cpu memory controller or something? I just bought this ram and sold my gskill 32Gb 3200mhz c14 kit so I could fit the massive D15 in my case, so I could do this cpu overclock..what is the benefit of slower ram in this case?

-I don't want to destroy my system or significantly degrade it, It is my daily driver but I do want some gains.. I've been wasting this delidded chips potential for the 3 years I have had it. I will in all likelihood probably upgrade in a year after Alder lake drops.

-How certain are you about that 1.3 volts? I read this massive guide: https://forums.tomshardware.com/threads/intel-cpu-temperature-guide-2021.1488337/
and there is a graph a ways down showing 1.4v as the level that you risk degradation for 14nm chips, the 22nm chips do risk degradation at 1.3v though according to that.

- My biggest concern is data loss/corruption. So I want to be darn sure I am stable enough to prevent that. I do music production and some light photo editing and then gaming. Those would be my daily use cases.
 
Yes, lowering the memory speed DOES reduce stress on the IMC, which of course is inside the CPU. So that tends to reduce some factors that can cause a CPU to overheat or become unstable, however, I never recommend doing that unless it's absolutely necessary.

Better to run your memory at it's INTENDED frequency, timings and voltage and reduce your CPU overclock a bit than the other way around. I would never recommend reducing your CPU configuration to a level that is below it's intended advertised configuration but sometimes you have to take the gains you can get.

As far as the information and question from your PM the only question or response I could offer would be, DID you perform the extensive testing procedures that I recommended in my overclocking guide? If you did, and your voltage was lower than the Intel temperature guide recommends as a maximum AND you stayed within the recommended thermal limit AND you had no errors, after running the recommended tests, ALL of them, then I'd say you are good to go so long as you don't notice any other irregularities. Not every CPU is the same AND delidding changes a lot of the behaviors and characteristics but even so I'd still try to comply with the recommendations in the ITG.

I'm rather doubtful of the stability with those configuration settings, but it's certainly possible. Do the testing. The work tells the story.
 

_dawn_chorus_

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Yes, lowering the memory speed DOES reduce stress on the IMC, which of course is inside the CPU. So that tends to reduce some factors that can cause a CPU to overheat or become unstable, however, I never recommend doing that unless it's absolutely necessary.

Better to run your memory at it's INTENDED frequency, timings and voltage and reduce your CPU overclock a bit than the other way around. I would never recommend reducing your CPU configuration to a level that is below it's intended advertised configuration but sometimes you have to take the gains you can get.

As far as the information and question from your PM the only question or response I could offer would be, DID you perform the extensive testing procedures that I recommended in my overclocking guide? If you did, and your voltage was lower than the Intel temperature guide recommends as a maximum AND you stayed within the recommended thermal limit AND you had no errors, after running the recommended tests, ALL of them, then I'd say you are good to go so long as you don't notice any other irregularities. Not every CPU is the same AND delidding changes a lot of the behaviors and characteristics but even so I'd still try to comply with the recommendations in the ITG.

I'm rather doubtful of the stability with those configuration settings, but it's certainly possible. Do the testing. The work tells the story.

-Any setting in particular that makes you doubt the stability? Just the clock and voltage? I am less confident about the other settings, some I have disabled based on other tutorials.

-You recommend dialing down the oc if you are hitting 80c+ in the small fft/avx off thermal test. If the TJmax is over 100 c , why be this conservative? I did allow mine to hover in the mid 80's for that test and realbench as well. But idle I am in the mid 30's and under a heavy cpu hungry game only at 65c.

-I didn't have an option to change CPU Ratio to "per core" as mentioned, but would like the CPU to operate that way. Is there another setting that would change that?

-I will have to wait for a day off to do the 8 hours of each stress test, as recommended by your guide. So far an hour of each has been passed. But that will be the ultimate answer.
 
If you are using offsets, then that might change things a bit, if you are testing with no offsets but plan to use offsets after testing because obviously the use of AVX in games or applications would then not be likely to reach the same thermal peak as with it enabled.

For the purpose of longevity alone, I would certainly never allow a daily driver to be overclocked to a level where it is seeing, at most, 85°C. If you look at the data in the intel temperature guide you'll find that due to thermal degradation and VT shift it specifically says this:

If your hottest Core is near its specified Tj Max Throttle temperature, then your CPU is already too hot. The consensus among well informed and highly experienced reviewers, system builders and expert overclockers, is that it's prudent to observe a reasonable thermal margin below Throttle temperature for ultimate stability, performance and longevity. So regardless of environmental conditions, hardware configurations, software workloads or any other variables, Core temperatures above 85°C are not recommended.

And, that should be during testing. You don't want to configure your CPU to reach 95°C during testing "because you know it will never reach that temp in real world use" because actually, you don't know that. I and many others have definitely seen it happen. Now, if this was a CPU you were just playing around with and had no concern for whether it lasts or not, then by all means, cook it. But don't do it for any daily driver or valued system. Obviously, that is just my opinion, but it's backed up by a wealth of resources including the Intel temperature guide which I believe to be the definitive informational resource on Intel processor temperatures and specifications related to them. But of course, it's your CPU, you can assuredly make your own decisions in that regard. We simply make those recommendations based on what we've seen, experienced and in the case of Computronix, what his extensive testing has determined, to be the safe zone. Not everybody likes to play it safe, or safe-ish rather, so that's something you have to decide for yourself.

Keep in mind though, that unless you are monitoring CPU temps 100% of the time, you really don't know if at some point you'll run something that may exceed the loads your system normally handles which is why we recommend having a moderate buffer there.

You'll need to look through the advanced settings on the tweaker tab, but there SHOULD be a setting in there to set frequency per core. Also, I highly recommend disabling Intel Speedshift and enabling Intel Speedstep, along with setting the C-states to their auto settings or leaving them enabled. Again, that's up to you, but more often than not you'll see lower overall peak temps under identical loads if the core gets a chance to relax down to a minimal frequency and voltage when not needed, which will usually be periods of microseconds under good loads, rather than always being at a static higher frequency or not allowed to reduce below base clock speed as some people prefer. CPUs can go from 800mhz to 5Ghz faster than any person could notice the change so in that regard there should never be any lag and if you under a full on fairly continuous load it's unlikely that any core that is needed will drop it's speed anyhow.

Again, those are my preferences. You may prefer to do things differently. The reason I have some doubts on stability with those settings, and I'm not saying it is NOT stable, I'm just saying, do the work to be sure, is because of what I've typically seen others able to achieve stability at and the fact that my only 4 core 4 hyperthread 6700k requires 1.35v for a 4.6Ghz all core OC. I know there have been SOME refinements to the architecture since then, but not much. It is still Skylake 14nm architecture at the end of the day. So, four additional cores with a moderately higher overclock SHOULD typically require more voltage, but testing will tell you the truth for YOUR CPU because every one is different. And, as I said, there have been refinements since the initial 6th Gen Skylake products.
 
Solution

_dawn_chorus_

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Thanks for all the help and information everyone, it was a fun couple weeks I spent trying to sort it all out. I kept getting "stable results" at lower and lower vcore but was surprised at how little the performance gains actually felt in my real world use cases. After seeing several people on various OC forums saying "I've seen failures in the 47th hour of prime95 runs" or something similar I just decided this small almost unnoticeable performance gain doesn't seem worth risking the stability of my system since this is my daily driver, nor do I want to spend so much time trying to determine if it will remain stable. I may give it a go once I move all of my important work to a new system and just have games on this one.