Question I9 9900k few cores (random ones) are like every 3 secs slowing down to 4,5-4,6 GHz, where could be the problem?

imicek

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Hey there, I already asked something about the I9 temperature before.
Now I removed the CPU fan, turned it 90° to the right direction (I set it before wrongly), and also removed and applied the thermal paste again.
Now the cpu seems stable with only like 35° on 5.0 GHz If I'm only writing this post, "BUT", if I'm watching all the core speeds, It's somehow synchronized, but time to time (like every 3 secs) one or few cores drop to like 4,5-4,6 GHz.
If I run the cinebench, I got only 2051 cb, which is almost 100 less than the average I9 should have. Also the temperatures are max 75°C while running cinebench.
I set the CPU voltage to 1.28 V manually, but It's now sitting at 1.261 V and time to time drops to 1.252 V.
What should I do to make it somehow more "stable" with all It's cores?
 
Actually, that's what it SHOULD do. In fact, I'd go into the BIOS and under the the CPU settings make sure that it is set to "per core" rather than sync, if that option exists on your motherboard. I'd also set the Windows power options power plan to performance, and then go into the advanced settings for that power plan and set the min processor power state to 8% while leaving the maximum setting at 100%.

Even under full load conditions, you will sometimes see a core or it's hyperthread not carrying a full load. Much of that behavior is down to the motherboard and how it was designed to handle core enhancements when XMP is enabled. Most board manufacturers do not adhere to the Intel core behavior guidelines and just do their own thing, so when enabling XMP I always recommend that you say NO when asked if you want to apply the "core enhancements" as well, IF that board asks you that.
 

imicek

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so when enabling XMP I always recommend that you say NO when asked if you want to apply the "core enhancements" as well, IF that board asks you that.
Already did that as you say.

Actually, that's what it SHOULD do. In fact, I'd go into the BIOS and under the the CPU settings make sure that it is set to "per core" rather than sync, if that option exists on your motherboard.
I have actually a ASUS ROG Maximus XI Hero and I have sync all cores on (now).

I'd also set the Windows power options power plan to performance, and then go into the advanced settings for that power plan and set the min processor power state to 8% while leaving the maximum setting at 100%.
Isn't better to go with 100% min and 100% max? (I think I'm using that rn.)
 
You should not be messing with min and max, default settings in Balanced mode is correct....

And, certainly under load at 5 GHz, you will not be seeing any 35C temps, as that temp would only apply to idle conditions when at 800-1000 MHz clock speeds...

Your mainboard might employ a TDP/power budget of 95 watts or so, which might limit your clock speeds somewhat...

If your cooling and power budget allows, 4.6 GHz all-core is expected behavior...(enabling MCE mode in the BIOS will boost this higher to as high as the 5 GHz (effectively making your CPU a 9900KS even before it's launch!) if power budget and cooling solutions allow.. (this might require a slight core voltage bump to achieve with stability, however, and is certainly not a certainty on default core voltage)
 

imicek

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I'm playing rn Far Cry 4, everything maxxed out on ultra, 4k res and max processor temps are 63°C.

I have Noctua NH-D15, Fractal Design Define R6 with 3x140 of their fans.
 
You should not be messing with min and max, default settings in Balanced mode is correct....

This isn't an AMD build. There are no requirements OR recommendations for having to use balanced power plans on Intel platforms. I NEVER do that, on ANY Intel platform. I always set it to the Performance plan and then drop the min setting to 8% so that the power saving C states and Speed step features are not defeated. The miniscule benefits from having a FULL TIME full speed core frequency are far outweighed by the "rest" periods that individual cores are able to have when they are not required to be at full frequency all the time. The amount of time it takes a core to initially go from "idle" to full speed is along the order of .5ms, which is way faster than any human being could ever "notice" or appreciate when a load is suddenly presented. At least, for most people. There are a few "Super nerds" among us who claim to be able to tell the difference, but I believe that to be a wild exaggeration because I'm pretty sensitive to such things and I've tried a variety of applied loads and benchmarks and I do not see any discernible difference in performance or scoring when comparing a full time clock speed configuration (100/100) versus a relaxed one (8-10/100).

So to say that somebody shouldn't be "messing" with the processor power states, is to say the least, not an accurate assessment. Perhaps if you are using a laptop, then using the balanced plan is a good idea but for reasons OTHER than those we are concerned with on a desktop where battery life is not a consideration.


Think of it this way, in terms of WHY we do this.

You could drive your car around with the engine revved up to 3500 RPMs at all times, and that power would only actually get transmitted to the wheels when the clutch is engaged, but the rest of the time it isn't needed to be so high. Unnecessary wear, high engine temperatures and so on are going to happen. It's the same.

Your CPU's engine does not need to be at maximum RPMs while you are at a stop light. When you are driving, sure, but you wouldn't sit at the stop light with the engine racing just waiting for the light to change. Well, maybe if you were drag racing. The engine is going to wear out a LOT faster that way, and the longevity of cores is also affected by being at full clocks at all time whether there is actually a load applied or not because they don't get those moments or extended periods of inactivity to allow those unused cores to cool and relax. It's been proven that reduced clock speeds and voltages, will reduce power consumption and thermal degradation, over time, so considering there is absolutely no measurable negative reasons for not doing that, it makes no sense to run the engine at full speed when it isn't needed.
 
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imicek

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Sep 22, 2019
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All right ten, will change that, buf we have the same issue with the core slowing down. :-D I was also thinking, If It's fine at 5 or I should go for like 5.1 as I'm somehow running it relatively fine.
 
If you are running that 9900k at 5Ghz on all cores, I seriously doubt it's either stable OR thermally compliant, unless you have exceptional cooling AND have run through the very lengthy process of establishing stability through rigorous stress testing. Everybody "thinks" they have had the luck of the draw and got the "magic" chip when they first start out. Little do they first realize that there is far more involved than just click click, boom, quick test, all good. No, it doesn't work that way. Ever.

Please list your FULL hardware specifications including CPU cooler model, number and model of case fans, case fan locations, DIRECTION of airflow for each case fan, case model and what steps you have taken so far to test thermal compliance and stability including exactly what programs you have used to make that determination, what modes were used and for how long they were run.

Or, to make things even more abundantly clear, you should read this and if you haven't done everything indicated there, or some process that is especially similar TO it, then you still have a lot of work ahead of you. And the first indicator that you're barking up the wrong tree is the fact that you've tried to jump directly to an all core 5Ghz overclock rather than starting with something less dramatic like an all core 4.7Ghz OC and worked your way up from there, testing at each phase along the way.




Pics in there will be fixed soon, but it shouldn't have any bearing on the material.