Looking for some help understanding LLC and advice for my 5Ghz Overclock :)

[Zammin]

Hi everyone!

You guys were a huge help in assisting me when dialing in my 4.8Ghz Adaptive mode OC previously. I really appreciate the help.

My 8700k now has liquid metal between the die and the IHS, giving me more temperature headroom for overclocking. It's also being watercooled (along with my 1080Ti by 2 360mm radiators in a fairly compact case.

My previous settings for 4.8Ghz was Adaptive Voltage mode (setup as per the instructions by Raja here: http://edgeup.asus.com/2017/kaby-lake-overclocking-guide/3/?_ga=2.185832041.1973363672.1518950532-88...) with a maximum turbo voltage of 1.275V in BIOS, no AVX offset and an LLC level 4, this led to a load voltage of 1.232V.

I am using ROG CPU-Z, AIDA64 and iCUE to read stats.

I have done some playing around with overclocks since building my new rig and was able to achieve 4.9Ghz with an adaptive voltage of 1.295V +0.010 offset in BIOS, no AVX offset and an LLC level 4, which gave me a load voltage of 1.248V.

I am now shooting for 5Ghz but have been unsuccessful to reach this with LLC as the voltage droop is too much at higher voltages. I can achieve it with no AVX offset at Adaptive 1.370V BIOS and LLC5 which gives me about 1.350V under load in AIDA64 FPU Stress Test (AVX) or I can achieve 5Ghz with an AVX offset of -1, an adaptive voltage of 1.350V in BIOS and LLC5 which gives me a load voltage of 1.30-1.31V in Prime95 26.6 (no AVX) and 1.30V in AIDA64 FPU (AVX).

I am however a little confused about LLC though. I understand the purpose of LLC is to control the level of Vdroop when the CPU is under load. However higher LLC levels can lead to higher overshoot, but this overshoot is not measurable by software and requires the use of an oscilloscope. This leaves me with confusion about how high you can go with LLC levels before it's unsafe for daily use. I get the impression that the LLC4 is insufficient at these higher voltages because the Vdroop is more dramatic than it was at lower voltages (my 4.8Ghz OC for example), and using LLC5 brings it back to a more acceptable amount of Vdroop.

So my question is, does anyone know if LLC5 is safe for me to use at my current overclock? (5Ghz -1AVX)

Is there a way to know what is an isn't safe without an oscilloscope or other specialised equipment?

Do you have any advice for me regarding my current overclock settings? (BIOS screenshots incoming).

And finally, what does the offset value in Adaptive voltage really do? does it apply an offset to the entire curve like Offset Mode does? is there any reason to add a voltage offset under adaptive mode when you can just increase the maximum turbo voltage by the same amount?

Thanks a lot in advance, and sorry for all the noob questions.

[Zammin]

[Zammin]

Also I'm currently trying to overclock the CPU cache/uncore ratio and I've started at 45 and stepped my way up to 47, but at 47 when under load it drops back to 46.. Does anyone know why this is or how to prevent it?

[Rozov]

Hi guys, I have a question about LLC behavior on z170a -
here's thing, i'm running on oced 6700k to 46, curently adaptive 1.32 +offset 0.008 so I got 1.328v on vcore (vids 1.330) at full load, LLC is on auto so i have no vdroop at load, it's stady and stable, so my question is - does it in my case working at max level being on auto, and\or (logicaly) is it possible for LLC to be off on auto? O_O

[Zammin]

I have changed some settings on my 5Ghz overclock due to the AVX offset constantly kicking in during gaming. I'm at the same voltage and LLC but I've increased the CPU current capability to 140%, raised the cache ratio to 46 (any higher causes instability) and changed the AVX offset to 0. I have run 45mins of AIDA64 and 1 hour of the latest Realbench without issues. Very pleased. I would still like to understand some of these settings better though, if anyone has the time to help me out.

[Rozov]

Zammin wrote:
I have changed some settings on my 5Ghz overclock due to the AVX offset constantly kicking in during gaming. I'm at the same voltage and LLC but I've increased the CPU current capability to 140%, raised the cache ratio to 46 (any higher causes instability) and changed the AVX offset to 0. I have run 45mins of AIDA64 and 1 hour of the latest Realbench without issues. Very pleased. I would still like to understand some of these settings better though, if anyone has the time to help me out.

Where did you changed avx offset?
I've made an experiment with LLc it occures that when it's set on auto it doesn't drop corevoltage at load (tho it still randomly spike to about +0.016 (1.344) so I've turned llc to 7 (which is highest on my mobo) to see if that's what sets my chip on to this behavior and you know what it's dropping voltage from 1.328 to 1.312 at load and it also frickin spikes to same 1.344 wtf?! same's with llc6.
So what's the point using it at all if it's dropping even on max sett and also spikes, though when it's on auto it's not droping but spiking to the same value. Also i figured that if i downvolt a bit to 1.320 it will spike to 1.328 so that's 0.008 against 0.016, so the higher the voltage and these spikes grows exponentially.
What am I missing here?
I'll try to lower llc to 5 and see if the spikes will occure again, but man i don't want vdrop to much

[NemesisChild]

Rozov wrote:
Where did you changed avx offset?
I've made an experiment with LLc it occures that when it's set on auto it doesn't drop corevoltage at load (tho it still randomly spike to about +0.016 (1.344) so I've turned llc to 7 (which is highest on my mobo) to see if that's what sets my chip on to this behavior and you know what it's dropping voltage from 1.328 to 1.312 at load and it also frickin spikes to same 1.344 wtf?! same's with llc6.
So what's the point using it at all if it's dropping even on max sett and also spikes, though when it's on auto it's not droping but spiking to the same value. Also i figured that if i downvolt a bit to 1.320 it will spike to 1.328 so that's 0.008 against 0.016, so the higher the voltage and these spikes grows exponentially.
What am I missing here?
I'll try to lower llc to 5 and see if the spikes will occure again, but man i don't want vdrop to much

AVX offset is not a bios option on the Z170 chipset.

[Zammin]

Rozov wrote:
Where did you changed avx offset?
I've made an experiment with LLc it occures that when it's set on auto it doesn't drop corevoltage at load (tho it still randomly spike to about +0.016 (1.344) so I've turned llc to 7 (which is highest on my mobo) to see if that's what sets my chip on to this behavior and you know what it's dropping voltage from 1.328 to 1.312 at load and it also frickin spikes to same 1.344 wtf?! same's with llc6.
So what's the point using it at all if it's dropping even on max sett and also spikes, though when it's on auto it's not droping but spiking to the same value. Also i figured that if i downvolt a bit to 1.320 it will spike to 1.328 so that's 0.008 against 0.016, so the higher the voltage and these spikes grows exponentially.
What am I missing here?
I'll try to lower llc to 5 and see if the spikes will occure again, but man i don't want vdrop to much

I'm not sure if your motherboard has AVX offset but you can see it in my first bios screenshot. Normally it is on Auto or 0 by default.

LLC7 is quite high and you may be at risk of severe overshoot, but as I mentioned in the original post I don't fully understand how to determine this since these overshoots can't be detected by software. I remember reading in an older post by Raja where he generally recommends LLC4 and LLC5 for daily use. I believe Der8auer also mentions LLC5 being safer than LLC6 for daily use as well in his 8700k overclocking guide video.

When I leave LLC on auto I get very severe Vdroop at these higher voltages, I find that under 1.30V LLC4 seems to keep vdroop in check and above 1.30V LLC5 seems to do the trick. I usually aim for around a 0.020v-0.040V vdroop during stress tests as I find this to be the most stable, however as I previously mentioned I don't know why this is as I don't fully understand LLC. I found this simply through trail and error. For example My first overclock on this chip was 4.8Ghz @ 1.275V manual voltage override and LLC6 which held the voltage at the set amount during stress tests (no vdroop detected in software), anything under this voltage would crash. However when I set up adaptive voltage I tried LLC4 at the same voltage which brought the voltage down to 1.232V under full load and it was totally stable.

It seems very strange that you are seeing vdroop on the highest LLC setting when that normally results in overshoot, but having said that we are on different CPUs and Chipsets so I can't be too sure. You're probably better off starting your own thread as you'll be more likely to get direct responses there.

[Rozov]

Zammin wrote:
I'm not sure if your motherboard has AVX offset but you can see it in my first bios screenshot. Normally it is on Auto or 0 by default.

LLC7 is quite high and you may be at risk of severe overshoot, but as I mentioned in the original post I don't fully understand how to determine this since these overshoots can't be detected by software. I remember reading in an older post by Raja where he generally recommends LLC4 and LLC5 for daily use. I believe Der8auer also mentions LLC5 being safer than LLC6 for daily use as well in his 8700k overclocking guide video.

When I leave LLC on auto I get very severe Vdroop at these higher voltages, I find that under 1.30V LLC4 seems to keep vdroop in check and above 1.30V LLC5 seems to do the trick. I usually aim for around a 0.020v-0.040V vdroop during stress tests as I find this to be the most stable, however as I previously mentioned I don't know why this is as I don't fully understand LLC. I found this simply through trail and error. For example My first overclock on this chip was 4.8Ghz @ 1.275V manual voltage override and LLC6 which held the voltage at the set amount during stress tests (no vdroop detected in software), anything under this voltage would crash. However when I set up adaptive voltage I tried LLC4 at the same voltage which brought the voltage down to 1.232V under full load and it was totally stable.

It seems very strange that you are seeing vdroop on the highest LLC setting when that normally results in overshoot, but having said that we are on different CPUs and Chipsets so I can't be too sure. You're probably better off starting your own thread as you'll be more likely to get direct responses there.

Thank you for the input!

[Carlyle2020]

hello there,

i have a similar setup @5 Ghrz.
I run:
VCCIO @ 1.2 after fiddling around with it a long time
edit:
Forget the rest. Try above and use your experience so far an try stuff that did barely start before.


...forgetable rest:
agent@1.175 - this value does not matter concerning your question(s) . I believe you can get away with what you use 😉

RAM: Corsair/old Hynix 🙂 @45ms/450 - 16GB @3200 orig. with 1.3450. Now bumped to 1.3500 @ 15/17/34
CPU Cache 8/47
AVX 0, because AVX1-10 introduces an extra "step" while clocking down and up. (In my experience). I find that extra step not usefull.
adaptive with 1.285 - leads to plus 0.050 (1.335 which would be my per-CPU-vid shown, beside my value CPU vcore 1.285) in some tests lile AIDA Stresstest, Firestrike.
Cinebench runs @ 1.285
I always used LLC 4 - works for me and should be fine longterm - from what i could gather through the interwebs
MCE auto, not off. Which should make not difference they say...
i maxed my package power time window (9999)

BLK Aware Adaptive Voltage: ... .. .
🙂 just for funsies check your agent live voltage and turn it off. MY voltage rises a little. So i also turn it on auto.. like MCE .
Modus 1 - in the RAM section. Makes no difference with my RAM kit to be honest. I ran 3 months Modus 2. Der8auer has an opinion on this as well (Modus 2..i think).

Have fun fiddling around. I always have 🙂
Rgds Carlyle