[SOLVED] 9900k Unstable overclock when not under load

YoitsTmac

Commendable
Feb 18, 2019
8
0
1,510
Hi everyone! This is my first serious computer and I'm having trouble stabilizing the system. I would really appreciate some help.
Here's my symptoms: Suddenly, out of nowhere, my RAM XMP profile now causes the system to boot loop about 8 times before it'll post. I just removed the XMP profile (Corsair Vengeance 3000Mhz), but its a bit of a bummer that I'm at 2133Mhz.
More importantly, the overclock seems unstable. My temps are really good but after about 8 minutes of stress testing, the power will suddenly jump from ~120W to 230W with no change in clock or performance. I'm not sure if this behavior is normal but I'm I don't experience these jumps in gaming or video editing.
Additionally, it seems sometimes when the system is idle or under low load, it will freeze in entirety. I tried DL a game overnight but it seemed to freeze about 10-15 mins in (just an example)
I have a 9900k in a Z390 with the following settings:
  • CPU Core Ratio all set to 4.8Ghz
  • CPU Core as manual at 1.23V
  • CPU C-states: enabled
  • Enhanced CPU C-States: Enabled
  • Package C state Limit: C7
  • CPU C7 Report: C7s
  • ASUS MultiCore Enhancement: Auto
  • AVX offset: 0
  • IA Load Line (DC and AC): 0.01
  • Duration Package Power Limit (long and short): 4095
  • Package Power Time Window: 127
  • Intel SpeedStep: Auto
  • Turbo Mode: Enabled
  • CPU Current Capability 130%
  • CPU Load-line Calibration: Auto
I think that's all that is relevant. Any help would be appreciated. I assume perhaps making the voltage setting somehow variable would likely help.

Edit: Board is a ASUS Z390i
 
Last edited:
Solution
Change the auto offset to some small positive value, or increase Load Line up again. Probably just not enough voltage to run 4.8Ghz under a heavy load (though I would expect it to back itself off). Monitor voltage and keep it below 1.3.

With MCE off, now it is using the normal boost patterns instead of boosting all cores.

Eximo

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Auto Load Line is probably helping you out under a heavy load and inactive under a low load, and you are just on the border of stability with the core voltage.

Increase CPU core voltage. 1.23 seems low for all core 4.8Ghz.

Load Line will result in more voltage than set manually, so there is some caution to be had with a fixed core clock. Also not letting the CPU run down to a lower voltage when you don't need it. (Something I do as well, but my machine is basically only for gaming, and the occasional MS office related task)
 

YoitsTmac

Commendable
Feb 18, 2019
8
0
1,510
Thanks for your comments. Would you suggest I turn Load Line off to determine what is truly the correct voltage for my clock speeds, or to somehow set an adjustable voltage? I see there's like a "add voltage" and "lower voltage" part of BIOS, but I don't know when the BIOS will use those settings IE. If set to 1V and told it can add 0.24V, if it will add that voltage when under load. And on the flip side, why that would be preferable over the "lower voltage" mode, where you set it to 1.24V and tell it it can lower by 0.24V.

This CPU was de-lidded by silicon lottery, I'm not sure if that helps with voltage. I also saw Optimum Tech was able to get a 9900k to 4.8Ghz all-core at 1.13V, so I figured this was pretty standard OC voltage:
View: https://youtu.be/k91u4uy4XvM?t=225


This is my main rig and I actually do work on it. So it's a little upsetting when it's sitting idle and I return to it frozen. How do
 

Zerk2012

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Thanks for your comments. Would you suggest I turn Load Line off to determine what is truly the correct voltage for my clock speeds, or to somehow set an adjustable voltage? I see there's like a "add voltage" and "lower voltage" part of BIOS, but I don't know when the BIOS will use those settings IE. If set to 1V and told it can add 0.24V, if it will add that voltage when under load. And on the flip side, why that would be preferable over the "lower voltage" mode, where you set it to 1.24V and tell it it can lower by 0.24V.

This CPU was de-lidded by silicon lottery, I'm not sure if that helps with voltage. I also saw Optimum Tech was able to get a 9900k to 4.8Ghz all-core at 1.13V, so I figured this was pretty standard OC voltage:
View: https://youtu.be/k91u4uy4XvM?t=225


This is my main rig and I actually do work on it. So it's a little upsetting when it's sitting idle and I return to it frozen. How do
9900K4.80GHz4.60GHz1.275V100%
9900K4.90GHz4.70GHz1.287VTop 91%
9900K5.00GHz4.80GHz1.300VTop 30%
9900K5.10GHz4.90GHz1.312VTop 5%

https://siliconlottery.com/pages/statistics

Don't believe everything you see on youtube.
 

YoitsTmac

Commendable
Feb 18, 2019
8
0
1,510
I got the 9900k off r/hardwareswap. All I as for stability is it will do 5.1 at 1.32V in relation to stability.

So even if I up my voltage and that makes it stable at idle, should I do anything with Load line ? And in relation to voltage, what type of Voltage mode is recommended for a main computer? I know there's add, subtract, auto, manual and adaptive. I have read a lot that auto will do any voltage it wants and can be concerning
 

Zerk2012

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I got the 9900k off r/hardwareswap. All I as for stability is it will do 5.1 at 1.32V in relation to stability.

So even if I up my voltage and that makes it stable at idle, should I do anything with Load line ? And in relation to voltage, what type of Voltage mode is recommended for a main computer? I know there's add, subtract, auto, manual and adaptive. I have read a lot that auto will do any voltage it wants and can be concerning
Google your motherboard and add overclocking 9900K

EDIT you do see only the top 5% of the processors tested could do 5.1 at that voltage.
 

Eximo

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Agreed, a good overclocking guide will help out here. Skylake through Coffeelake are pretty interchangeable when it comes to voltages and most features.

I would set load line to a low value if you are going to stick with 4.8Ghz all core, but take the core voltage to something like 1.28. That should still stay pretty cool and give you added stability. CPU might be better than that, but only testing it will tell you that (and there will be crashing if you aim for minimum voltage to get the job done)
 

YoitsTmac

Commendable
Feb 18, 2019
8
0
1,510
I did google my MB and OC but a lot are questions about how to get 5 or 5.1Ghz, which MB to grab, the cooling and performance of the board. I got my current settings by following someone doing 5Ghz on my board and lowered values because I'm not going for insane speed, just a modest OC with good, quiet performance. My SFFPC is nice and quiet with the current settings even at full tilt thankfully.

I will adjust my load line and up my voltage and then do a stress test. It's an ASUS Z390i board, If a manually set Voltage isn't the best for a computer that regularly sees low loads, what is the preferred method for varying voltage while holding stability?
 

MonsterMaxx

Distinguished
Jan 23, 2015
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18,615
If you are going to overclock, you need to disable Turbo. You are turbo'ing the machine with your overclock, then under a load the machine turbos again. =Crash.

What are you using to stress test? I'm not a fan of long runs of artificial tests. 2min is all you need.

My 9900k runs 5.0 on all cores and I max out around 175°F with the H100i water cooling with 2min of P95.
 

YoitsTmac

Commendable
Feb 18, 2019
8
0
1,510
Voltage offsets.

Basically just adds voltage on top of the current range that the CPU will run automatically.

Also dangerous at the top end if set to high, the CPU can exceed what is considered safe.
What is the baseline voltage? Or what would it be called in BIOS? I saw I can request to add voltage, but I don't know what voltage I'm adding to. Also I saw the Load line asks me to request which C-State it should calibrate to? I assume it should calibrate off a lower state like C3?


If you are going to overclock, you need to disable Turbo. You are turbo'ing the machine with your overclock, then under a load the machine turbos again. =Crash.

What are you using to stress test? I'm not a fan of long runs of artificial tests. 2min is all you need.

My 9900k runs 5.0 on all cores and I max out around 175°F with the H100i water cooling with 2min of P95.
I will disable turbo, thanks! I've been using Prime95. I was told 30 mins is good as you want the fluid of your loop saturated to get a better understanding of thermals, but unfortunately after about 8 minutes or so wattage doubles with no changes in clock and it gets really hard to even fight the temp. Otherwise I'm about 80C at 1,300rpm on my 240mm AIO at full load. In gaming environments it rests at about 60C and I get peaks as high as 85, oddly.
 

YoitsTmac

Commendable
Feb 18, 2019
8
0
1,510
Alright everyone, so here's what I adjusted.

I disabled ASUS Multicore enhancement, CLL to C-State 3, set CPU C-States to Auto, I kept Turbo enabled (things are good without changing it) and I set the V-Core to adaptive and set it to 1.27 with the offset as auto. Honestly, I have no idea what that means, or how it prevents my CPU from hitting say, 1.35V or something, but here's my results.

I'm drawing less power across the board. I had to max out my current limits to get my results but no problem at all.

At 4.7Ghz my V-Core "adapted" to 1.18V. At 4.8Ghz my V-Core "adapted" to 1.219 and holds steady there. My clock rate is still buried at 4.8Ghz all day, does not clock down. And I was stress testing and at about 5 minutes it blue-screened. Unless the cores clock down at idle and I can prevent a blue screen, I don't know how if this is really anything better than what I had.
 

Eximo

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Change the auto offset to some small positive value, or increase Load Line up again. Probably just not enough voltage to run 4.8Ghz under a heavy load (though I would expect it to back itself off). Monitor voltage and keep it below 1.3.

With MCE off, now it is using the normal boost patterns instead of boosting all cores.
 
Solution