[SOLVED] i9-9900k overclocking limits?

Jnelly99

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Nov 30, 2019
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1,510
Specs:
Mobo: Asus ROG Strix z390-E
CPU: i9-9900k
GPU: Gigabyte gtx 1080ti
PSU: 750w
Ram: 32gb 3600mhz

So i just finished my first custom water loop build and first build with the i9-9900k. This is going to be my first time manually overclocking and wanting to get the most out of my cpu with out it dieing out in 1 week. So far i have my overclock set to 5ghz at 1.3volts. After doing a stress test i get max temp of 79 Degrees. I mainly use the computer to stream and play games on with the once in awhile video/photo editing. When i launch call of duty modern warfare i get a max temp of about 70degress. Im wondering if this is a good over clock or would i be able to push it a little more like 5.1ghz at 1.3volts and get better performance or does it not really make a difference? I'm not to sure about the volts part of overclocking i know the higher the more heat and power it uses and not to do crazy high with it, but would i get better performance if i go like 1.25 volts and 5.1ghz or no?
 
Solution
You have a full custom loop. Toss out any preconceived ideas of temps based on standard aircooling behavior. They don't apply.

Intel cpu's have a working range of temp. And it's all the same. 40°C is exactly the same as 50 or 70°C to the cpu. It's only once you get into throttle temps ranges that things matter.

Loops are liquid and liquids have a very large capacity to absorb energy, but it's very slow to change. Aircoolers are a big chunk of metal and metal transfers heat very fast. Stick an empty pan on a 1500w stove burner, pan heats up extremely fast. Stick a pan full of water on same burner and you'll be waiting a good long while for the water to even get warm. And that's the difference. It doesn't matter what the exact temp of...
After "doing stress test" with WHAT? For how long?

Have you also tested stability? Really, have you?



Testing thermal compliance

Once you get to the Windows desktop, the first thing you will want to do is open HWinfo (Sensors only option) or CoreTemp and take a look at what your core and package temperatures are doing. At idle your core temps should be somewhere below 40°C. Preferably somewhere in the mid to low 30’s. This WILL be affected by whatever the ambient temperature is in the room where you are, so if your are in a very warm region and have no air conditioning going you may have an idle temp that is a bit closer to 40. For cooler ambient rooms or regions it will likely show low 30’s-ish. Be aware that unless you have excessively high idle temps, say, above 40°C, then what your actual idle temps are is practically irrelevant. Cooler idle temps are not indicative of much of anything specific.

Very HIGH idle temps however DO indicate that there is likely a problem with an incorrectly installed CPU cooler heatsink, too high of CPU core voltage or some other cooling or voltage related issue. If you are using one of those other utilities I warned about in the beginning of this tutorial, it may also be that the utility is reporting falsely. In that case, go get HWinfo or CoreTemp and check again.

If idle temps seem fine, then leave your monitoring application open and run Prime95 (Either version 26.6 or the latest version with AVX/AVX2 disabled).

Choose the Small FFT option (NOT "Smallest FFT") and allow it to run for fifteen minutes. If you are using the latest version of Prime95 (Version 29.8 or newer) then you NEED to be sure to disable the AVX and AVX2 options in the main options window. When you disable AVX2 the option to disable AVX will become available. If at any point your core or package temperatures exceed 80°C for Intel or AMD Ryzen platforms, then click the “Test” menu at the top of the Prime95 window and select “stop” or “exit”. Do not simply click the "X" in the top right corner as that will NOT stop the stress test, it will only minimize it to the tray.

You MUST click Stop or Exit from the drop down TEST menu at the top left of the window to stop the stress test.


If you have an AMD system, then measuring thermals is going to be a little different.

AMD does not design their platforms in a way that does not make, by any definition, measuring core temps accurate or reliable. On the low end of the scale their thermal sensor readings have long been laughable, sometimes showing temps that are well below what the ambient temperature is, which of course is not possible without some kind of Peltier cooler or active refrigeration. At the other end of the thermal range it’s not much better.

This is because AMD does not actually implement their sensor designs to be determined in the same way that Intel does. AMD uses a method known as distance to Tjmax. Tjmax being, in this case, the temperature at which AMD has determined bad stuff will start happening such as thermal throttling, shut downs and damage.

For this reason when you are testing thermal compliance, or just monitoring for general purposes, you need to be aware of this difference and purposely either use applications designed for use with AMD processors or make some settings changes in other utilities that will allow you to see distance to Tjmax rather than estimated core temps.

There are a couple of ways you can do this. First off, HWinfo generally has the appropriate fields which are labeled as Distance to Tjmax. I feel like the better choice though is either CoreTemp or AMD overdrive for monitoring Distance to Tjmax on AMD platforms. In CoreTemp you will need to go into the Options tab, click on Settings and on the Advanced tab check the box next to the setting for “Show distance to Tjmax in temperature fields” in order to change from the default and likely inaccurate core temperature display.

AMD overdrive shows Distance to Tjmax by default, and I don’t think there is any other way to monitor CPU thermals in that utility anyhow. Either of these is probably a good choice, but it’s also likely worth checking either CoreTemp or AMD overdrive against what you see for Distance to Tjmax in HWinfo and if the readings are pretty close to the same, just use HWinfo as there is a lot of other information available in the sensors display that is not available with these other two.

Regarding the actual Distance to Tjmax sensor readings, what you do NOT want to see is anything closer than 10°C Distance to Tjmax, ESPECIALLY if you are only in the first phase of your overclock configuration and have only made minor changes to the CPU multiplier and voltage at this point. If it drops below ten degrees to Tjmax you are getting very close to your thermal ceiling and need to revisit either your cooling solution or voltage settings.

If you can run the Prime95 version 26.6 or 29.8 (With AVX/AVX2 disabled) Small FFT torture test for 15 minutes without exceeding 80°C for Intel/AMD Ryzen or dropping below 10°C thermal margin (AKA Distance to Tjmax) for AMD, then you are to some degree or other within specification for thermal tolerance.

If you are very close to the edge however, this may be a warning sign that you don’t have much overclocking headroom since we’ve only barely set our multiplier to what is basically the all core equivalent of the default single core Turbo frequency (Speed). IF that is the case, you will want to either be very careful going forward or stop and think about upgrading your CPU cooler and perhaps looking at whether your case and case fan situation is really sufficient for what you are trying to do.






Stability testing

So, if you passed the thermal compliance phase the next step will be to test stability. I cannot over stress the importance of not cutting corners when it comes to stress testing. Do not listen to naysayers who try to tell you that if you simply run this or that for 15 minutes, or an hour, or can pass a specific benchmark without errors, that your system is stable. Do not listen to people who say that if it is only a gaming system then stability isn’t important so long as it doesn’t crash. This is unreliable.

It IS important, no matter WHAT you do on the system. Unstable CPU or memory configurations can thoroughly degrade an operating system, game files or other parts of your file system to the point of eventually making them unusable. Instability is also probably not the best thing for the hardware itself.
Do the tests. Do them for the length of time they should be done for and do not cut corners even though it is tempting to do. You will only be hurting yourself in the long run.

Open Realbench and run a 1 hour stress test to begin with. Choose the Stress test option by clicking on the Stress test button. Choose the one hour option. Set the memory option to approximately half of your total installed memory. We are not worried about testing memory right now. If you have more than 16GB of memory, choose the up to 16GB option. If you have 16GB of memory, choose the up to 8GB option. If you have 8GB or less, choose the up to 4GB option.

If you pass the 1 hour stress test and plan to try increasing your overclock a bit higher, then you can start again just as you did in the beginning but bump the CPU core frequency up by another 100-200mhz. If it will post and boot into windows, repeat the thermal test and the stress test.
If it will not POST and boot into windows, or if you get errors or bluescreens at any point, then you will need to bump up your CPU core voltage a bit and try again. We went over that in the beginning so that should be self explanatory at this point.


If you were not able to pass the one hour stress test, then also, you will want to go back into the bios and bump the voltage up a small amount. By small amount, I mean whatever minimal increment the BIOS will allow you to adjust it upwards in. If the voltage was at 1.32v and did not pass, or would not POST, or there were errors or bluescreens or the screen went black and (**)restarted then try bumping the CPU core voltage up to 1.325. If it was at 1.3v try 1.31. Etc.

(**Assuming it did not do so because of a low quality power supply. Very important to have a high quality power supply if you are going to be overclocking. Watts are not the only consideration. A unit with good, clean power that has low ripple and electrical noise is very important in order for the motherboard and voltage regulators to remain stable and not overheat as well.)

Every time you make a change in the bios to increase the CPU core voltage, YOU MUST RUN the thermal tests again to verify you are still within tolerance.

If however you passed the one hour stress test with no errors, no problems of any kind, and do not wish to raise the level of your overclock, or at any time if you get to the point where you are happy with the speed you have achieved up to that point, then you can go ahead and run the Realbench stress test again except this time run it for a full 8 hours.

If it passes that, then close Realbench and open Prime95 again. Choose the Blend test and run that for 8 hours. If it passes that, your system is probably about as stable as can be expected under almost any circumstances and you can call it a day if you are able to pass both of these tests and are still within thermal compliance. It’s worth noting that you may want to periodically check your maximum thermal readings on your monitoring software which you should leave running alongside any stress tests, just to make sure that you don’t exceed thermal limits while testing.

If you remained below the thermal ceiling when you ran the Small FFT Prime95 torture test though, you should not have any issues with thermals on either of these other tests anyway.
If you wish to take the stability testing one step further IN ADDITION to having passed both the Realbench 8 hr test and the Prime95 Blend mode 8 hr test, you can run Prime95 Small FFT for 24 hours and if you pass that there is little else you can do to assure that your system is stable in regard to your CPU overclock settings.

At this point you can move on to using your system normally again, or, if you wish to push things a little further to see how much more you can squeeze out of it, then you can simply start the whole process over again moving up incrementally from where you left off but it is terribly important that you always perform the thermal and stability tests after any changes so you don't end up creating tremendous problems for yourself later on or inadvertently damaging your hardware with an overclock that is beyond what your cooling system, motherboard and CPU are capable of sustaining.

If you have successfully achieved the overclock you were hoping for, then congratulations and at this point you can reconfigure your memory XMP settings or continue on to either tightening your memory timings or overclocking your memory, if you plan to do so.




Quick and dirty overview of overclocking validation procedure.

Set CPU multiplier and voltage at desired settings in BIOS. Do not use presets or automatic utilities. These will overcompensate on core and other voltages. It is much better to configure most core settings manually, and leave anything left over on auto until a later point in time if wish to come back and tweak settings such as cache (Uncore) frequency, System agent voltage, VCCIO (Internal memory controller) and memory speeds or timings (RAM) AFTER the CPU overclock is fully stable.

Save bios settings (As a new BIOS profile if your bios supports multiple profiles) and exit bios.

Boot into the Windows desktop environment. Download and install Prime95 version 26.6.

Download and install either HWinfo or CoreTemp.

Open HWinfo and run "Sensors only" or open CoreTemp.

Run Prime95, either version 26.6 OR the latest version WITH the AVX and AVX2 options disabled in the settings menu that pops up when you start up Prime95, and choose the "Small FFT test option". Run this for 15 minutes while monitoring your core/package temperatures to verify that you do not exceed the thermal specifications of your CPU.

(This should be considered to be 80°C for most generations of Intel processor and for current Ryzen CPUs. For older AMD FX and Phenom series, you should use a thermal monitor that has options for "Distance to TJmax" and you want to NOT see distance to TJmax drop below 10°C distance to TJmax. Anything that is MORE than 10°C distance to TJmax is within the allowed thermal envelope.)

If your CPU passes the thermal compliance test, move on to stability.

Download and install Realbench. Run Realbench and choose the Stress test option. Choose a value from the available memory (RAM) options that is equal to approximately half of your installed memory capacity. If you have 16GB, choose 8GB. If you have 8GB, choose 4GB, etc. Click start and allow the stability test to run for 8 hours. Do not plan to use the system for ANYTHING else while it is running. It will run realistic AVX and handbrake workloads and if it passes 8 hours of testing it is probably about as stable as you can reasonably expect.

If you wish to check stability further you can run 12-24 hours of Prime95 Blend mode or Small FFT.

You do not need to simultaneously run HWinfo or CoreTemp while running Realbench as you should have already performed the thermal compliance test PLUS Realbench will show current CPU temperatures while it is running.

If you run the additional stability test using Prime95 Blend/Small FFT modes for 12-24 hours, you will WANT to also run HWinfo alongside it. Monitor HWinfo periodically to verify that no cores/threads are showing less than 100% usage. If it is, then that worker has errored out and the test should be stopped.

If you find there are errors on ANY of the stability tests including Realbench or Prime95, or any other stress testing utility, you need to make a change in the bios. This could be either dropping the multiplier to a lower factor or increasing the voltage while leaving the multiplier the same. If you change voltage or multiplier at ANY time, you need to start over again at the beginning and verify thermal compliance again.
 
Although many might have success with all-core 5 GHz overclocks, fewer and fewer percentages of owners are successful much past that,with precious few being truly stable at 5.1-5.2 GHz, etc.. Each .05V core voltage increase and 100 MHz increase likely adds 5C to temps, and, I'd personally stay where you are if at a 70C-level in gaming loads, but,...it is your CPU,and, good luck!

70C temps would be quite reasonable (IMO) for a semi-intensive gaming load, but, you might want to see what tmeps are achieved with CPU-Z/bench/stress CPU after 15 minutes, or, the defacto heating/torture/stability standard will seemingly always be Prime95/smallFFTs (no AVX/AVX2). Many folks are lucky to stay under 85C under Prime95/small FFTs..
 
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zx128k

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Most 9900k cpu can't do 5GHz AVX, only really the 9900ks can do 5GHz AVX. The motherboard VRMs at vcore 1.3 volts use 25 watts at 200A @500KHz which is the 9900K maxed out. If you look at the table below, we don't need much more than 1.3 volts vcore for good silicon.

9900K4.80GHz4.60GHz1.275V100%
9900K4.90GHz4.70GHz1.287VTop 91%
9900K5.00GHz4.80GHz1.300VTop 30%
9900K5.10GHz4.90GHz1.312VTop 5%
9900KF4.80GHz4.60GHz1.275V100%
9900KF4.90GHz4.70GHz1.287VTop 92%
9900KF5.00GHz4.80GHz1.300VTop 37%
9900KF5.10GHz4.90GHz1.312VTop 8%
9900KS4.90GHz4.70GHz1.225V100%
9900KS5.00GHz4.80GHz1.250VTop 95%
9900KS5.10GHz4.90GHz1.287VTop 28%
9900KS5.20GHz5.0GHz1.325VTop 4%
https://siliconlottery.com/pages/statistics

Hopefully you have a thick 360 rad and full copper cpu block. Decent fans. 9900k gets very hot quickly. You are also going to need air flow over the VRM heat sinks beccause you are not using an air cooler.

Images from the Strix z390-e VRMs. https://www.guru3d.com/articles-pages/asus-rog-strix-z390-e-gaming-review,20.html Guru3d seems positive.

https://www.guru3d.com/articles_pages/asus_rog_strix_z390_e_gaming_review,20.html


Temps-1-1030x685.png

source Intel Core i9-9900K @ 5.3 GHz With 1.365V (100 x 53) The Intel Core i9-9900K when overclocked, breaches the 400W barrier.

I would make sure there is air flow over the vrm heatsinks which you should have normally. Don't go over 100C on the VRMs, keep below 100c.

7thJbb8.png


With a 750w you have no choice but to go for a moderate overclock. What PSU are you using? Make and model.
 

Jnelly99

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Nov 30, 2019
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Most 9900k cpu can't do 5GHz AVX, only really the 9900ks can do 5GHz AVX. The motherboard VRMs at vcore 1.3 volts use 25 watts at 200A @500KHz which is the 9900K maxed out. If you look at the table below, we don't need much more than 1.3 volts vcore for good silicon.

9900K4.80GHz4.60GHz1.275V100%
9900K4.90GHz4.70GHz1.287VTop 91%
9900K5.00GHz4.80GHz1.300VTop 30%
9900K5.10GHz4.90GHz1.312VTop 5%
9900KF4.80GHz4.60GHz1.275V100%
9900KF4.90GHz4.70GHz1.287VTop 92%
9900KF5.00GHz4.80GHz1.300VTop 37%
9900KF5.10GHz4.90GHz1.312VTop 8%
9900KS4.90GHz4.70GHz1.225V100%
9900KS5.00GHz4.80GHz1.250VTop 95%
9900KS5.10GHz4.90GHz1.287VTop 28%
9900KS5.20GHz5.0GHz1.325VTop 4%
https://siliconlottery.com/pages/statistics

Hopefully you have a thick 360 rad and full copper cpu block. Decent fans. 9900k gets very hot quickly. You are also going to need air flow over the VRM heat sinks beccause you are not using an air cooler.

Images from the Strix z390-e VRMs. https://www.guru3d.com/articles-pages/asus-rog-strix-z390-e-gaming-review,20.html Guru3d seems positive.

https://www.guru3d.com/articles_pages/asus_rog_strix_z390_e_gaming_review,20.html


Temps-1-1030x685.png

source Intel Core i9-9900K @ 5.3 GHz With 1.365V (100 x 53) The Intel Core i9-9900K when overclocked, breaches the 400W barrier.

I would make sure there is air flow over the vrm heatsinks which you should have normally. Don't go over 100C on the VRMs, keep below 100c.

7thJbb8.png


With a 750w you have no choice but to go for a moderate overclock. What PSU are you using? Make and model.
I got air flow over the vrms, got 7 fans in it and air flow seems to good. As for radaitors i got 2 360mm copper radaiators but they arent really that thick maybe like 2-3inches only, i thought that having 2 360mm with a alot of surface area would do about the same as 1 thicker one but i guess i could of been on the safe side and got 2 thick ones, would having thinner ones be an issue? And for power supple i have the corsair rm750x i thought that was plenty of power, is it not? And for cpu block i have the ek quantum velocity with copper nickle plated block, with thermal grizzly paste on it.
 
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zx128k

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I got air flow over the vrms, got 7 fans in it and air flow seems to good. As for radaitors i got 2 360mm copper radaiators but they arent really that thick maybe like 2-3inches only, i thought that having 2 360mm with a alot of surface area would do about the same as 1 thicker one but i guess i could of been on the safe side and got 2 thick ones, would having thinner ones be an issue? And for power supple i have the corsair rm750x i thought that was plenty of power, is it not? And for cpu block i have the ek quantum velocity with copper nickle plated block, with thermal grizzly paste on it.

9900k at 5Ghz can hit near 300 watts power draw.

tdauREAwqYvHhsTjDHesSH-970-80.png


Power-1.jpg


Temps-1.jpg

source

More here https://www.techspot.com/review/1744-core-i9-9900k-round-two/

This is why you need water cooling and a good PSU. You can easly pull 250 watts from just the CPU. This extra power your PSU will have to provide. Leaving less for the GPU etc. A 1080 ti can pull 280 watts. power 1080ti D5 pump is 22 Watts. 5-7w per fan. https://martinsliquidlab.wordpress.com/2012/12/06/xspc-d5-dual-bay-reservoir-combo/3/

Corsair rm750x is decent but you can get close to its maximum. Teir 1 https://www.gamingscan.com/psu-hierarchy/
 
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Jnelly99

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9900k at 5Ghz can hit near 300 watts power draw.

tdauREAwqYvHhsTjDHesSH-970-80.png


Power-1.jpg


Temps-1.jpg

source

More here https://www.techspot.com/review/1744-core-i9-9900k-round-two/

This is why you need water cooling and a good PSU. You can easly pull 250 watts from just the CPU. This extra power your PSU will have to provide. Leaving less for the GPU etc. A 1080 ti can pull 280 watts. power 1080ti D5 pump is 22 Watts. 5-7w per fan. https://martinsliquidlab.wordpress.com/2012/12/06/xspc-d5-dual-bay-reservoir-combo/3/

Corsair rm750x is decent but you can get close to its maximum. Teir 1 https://www.gamingscan.com/psu-hierarchy/
well after doing some prime 95 testing i have it down to 4.7ghz as 5 was not stable right off the start of the torture test. So far its not crashing on me only 2 hours into the test tho. 4,9ghz and 4.8 was stable off the start of the test but temps were up to 99-100 degress after like 15 mins but 4.7 is giving me 75-79 degress right now. I do have a custom water loop in my build, but for psu i will be buying a new one here soon.
 

Karadjgne

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You have a full custom loop. Toss out any preconceived ideas of temps based on standard aircooling behavior. They don't apply.

Intel cpu's have a working range of temp. And it's all the same. 40°C is exactly the same as 50 or 70°C to the cpu. It's only once you get into throttle temps ranges that things matter.

Loops are liquid and liquids have a very large capacity to absorb energy, but it's very slow to change. Aircoolers are a big chunk of metal and metal transfers heat very fast. Stick an empty pan on a 1500w stove burner, pan heats up extremely fast. Stick a pan full of water on same burner and you'll be waiting a good long while for the water to even get warm. And that's the difference. It doesn't matter what the exact temp of the cpu is, as long as it's within operating range, because it's temp will fluctuate every 256ms, whereas the loop can take a minimum of half an hour to fully saturate.

You see 70°C on a full core burn and are freaking out, based on opinions about temps with aircoolers as a basis. I see a 9900k at full burn on a loop and the temp is hitting 70°C, when most are lucky to keep temps under 90's.

A single standard 360mm rad has a capacity somewhere around 400w. Even a slim is @ 350w, the thick around 450w. With 2x standards, you have @ 800w worth of capacity, with @ 250w possible from cpu and 250w possible from gpu. 500w out of 800w possible is chump change. Easy. No worries on rads being large or thick enough.

9900k and 9900ks are the same cpu. There were some minor voltage tweaks internally but the biggest change was the turbo boost was changed from a single core turbo to all core turbo. With an all core OC, that negates that part totally, leaving just the internal voltage changes as relevant. Which doesn't change physical limits.
 
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Jnelly99

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Nov 30, 2019
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1,510
You have a full custom loop. Toss out any preconceived ideas of temps based on standard aircooling behavior. They don't apply.

Intel cpu's have a working range of temp. And it's all the same. 40°C is exactly the same as 50 or 70°C to the cpu. It's only once you get into throttle temps ranges that things matter.

Loops are liquid and liquids have a very large capacity to absorb energy, but it's very slow to change. Aircoolers are a big chunk of metal and metal transfers heat very fast. Stick an empty pan on a 1500w stove burner, pan heats up extremely fast. Stick a pan full of water on same burner and you'll be waiting a good long while for the water to even get warm. And that's the difference. It doesn't matter what the exact temp of the cpu is, as long as it's within operating range, because it's temp will fluctuate every 256ms, whereas the loop can take a minimum of half an hour to fully saturate.

You see 70°C on a full core burn and are freaking out, based on opinions about temps with aircoolers as a basis. I see a 9900k at full burn on a loop and the temp is hitting 70°C, when most are lucky to keep temps under 90's.

A single standard 360mm rad has a capacity somewhere around 400w. Even a slim is @ 350w, the thick around 450w. With 2x standards, you have @ 800w worth of capacity, with @ 250w possible from cpu and 250w possible from gpu. 500w out of 800w possible is chump change. Easy. No worries on rads being large or thick enough.

9900k and 9900ks are the same cpu. There were some minor voltage tweaks internally but the biggest change was the turbo boost was changed from a single core turbo to all core turbo. With an all core OC, that negates that part totally, leaving just the internal voltage changes as relevant. Which doesn't change physical limits.
Thank you that makes sense, im hitting max 80 degrees with prime95 running still so i should be good with the cooling in my system as it hasnt gotten any hotter and seems to be stable, i believe 4.7ghz at 1.2 volts is working good. Thank you for the information
 
80°C while Running Prime95 Small FFT, (which is the ONLY thing you should be running to test for thermals using Prime95 is "Small FFT" (Not "smallest fft", not blend, not large FFT), and you should be running it with AVX and AVX 2 disabled UNLESS you know you run games or applications that make HEAVY use of AVX, and then you should leave them enabled but use an offset in the BIOS), is fine. It is the very last "edge" of "fine", but it IS fine. If you are at 80°C while running Prime95 Small FFT then you are never going to see any game or application cause out of spec thermal conditions unless they use AVX instructions or something causes a change in your cooling performance.
 

zx128k

Reputable
PSU will get the job done, its not an issue. Here system load 360-400 watts https://wccftech.com/review/intel-core-i9-9900k-8-core-cpu-z390-aorus-master-review/9/ and add gpu.

With Prime 95 small fft's getting extreme temps is to be expected. Going right up to the edge is expected temp wise. In games you will be much lower. Worry if you do a lot of HEVC etc. You should run Aida64 for stress testing, like Darkbreeze states prime95 small fft's are great for people that need to test the cooling for heavy loads over a long deration of time. This is needed if you have to be stable, say you are running folding@home etc.

From the temps you state I would guess you have a version of prime95 with avx enabled. Sounds like 4.9Ghz is doable and 5GHz will take some work. If your PC is just for games you should be fine. Monitor your VRM's as well. Setting the VRM frequency to 500KHz can help too, default is normally 300KHz. The faster respoind helps keep things stable.

Basically HEVC is the same AVX load as Prime95 small fft's. Some HEVC loads hit my CPU like a hammer.

This image shows the cooling issue of prime 95 compared to aida64. Prime95 is 322 watts and Aida64 is 275.

9900kpowr-640x350.jpg

source

So test in aida64, it tests all the instructions. Prime95 just tests AVX and pulls maximum power. This is how your testing should look.

5141ghz-9900k.jpg.webp


Remember unlike AMD you can set an AVX offset to help with cooling if needed. You should go for 5GHz with an AVX offset. Start with 4.9GHz offset -1. You should be able to limit power draw as well.
 
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Jnelly99

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80°C while Running Prime95 Small FFT, (which is the ONLY thing you should be running to test for thermals using Prime95 is "Small FFT" (Not "smallest fft", not blend, not large FFT), and you should be running it with AVX and AVX 2 disabled UNLESS you know you run games or applications that make HEAVY use of AVX, and then you should leave them enabled but use an offset in the BIOS), is fine. It is the very last "edge" of "fine", but it IS fine. If you are at 80°C while running Prime95 Small FFT then you are never going to see any game or application cause out of spec thermal conditions unless they use AVX instructions or something causes a change in your cooling performance.
yes only running prime95 and small fft with avx disabled and only gettting 80 max at 4.7ghz 1.25 volts, so when i was running it for 15mins at 4.8 and 4.9 and getting 100 degrees max is normal then?
 

Jnelly99

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1,510
PSU will get the job done, its not an issue. Here system load 360-400 watts https://wccftech.com/review/intel-core-i9-9900k-8-core-cpu-z390-aorus-master-review/9/ and add gpu.

With Prime 95 small fft's getting extreme temps is to be expected. Going right up to the edge is expected temp wise. In games you will be much lower. Worry if you do a lot of HEVC etc. You should run Aida64 for stress testing, like Darkbreeze states prime95 small fft's are great for people that need to test the cooling for heavy loads over a long deration of time. This is needed if you have to be stable, say you are running folding@home etc.

From the temps you state I would guess you have a version of prime95 with avx enabled. Sounds like 4.9Ghz is doable and 5GHz will take some work. If your PC is just for games you should be fine. Monitor your VRM's as well. Setting the VRM frequency to 500KHz can help too, default is normally 300KHz. The faster respoind helps keep things stable.

Basically HEVC is the same AVX load as Prime95 small fft's. Some HEVC loads hit my CPU like a hammer.

This image shows the cooling issue of prime 95 compared to aida64. Prime95 is 322 watts and Aida64 is 275.

9900kpowr-640x350.jpg

source

So test in aida64, it tests all the instructions. Prime95 just tests AVX and pulls maximum power. This is how your testing should look.

5141ghz-9900k.jpg.webp


Remember unlike AMD you can set an AVX offset to help with cooling if needed. You should go for 5GHz with an AVX offset. Start with 4.9GHz offset -1. You should be able to limit power draw as well.
Yea i use my computer mainly for gaming and streaming, i will do a fully stress test with aida64 and see how that goes then with 4.9ghz. As for vrm's i was not monitoring the temps for those, and not sure how to adjust them in bios, i will look up some info and try that out too. hoping i can get 4.9ghz then.
 

zx128k

Reputable
Yea i use my computer mainly for gaming and streaming, i will do a fully stress test with aida64 and see how that goes then with 4.9ghz. As for vrm's i was not monitoring the temps for those, and not sure how to adjust them in bios, i will look up some info and try that out too. hoping i can get 4.9ghz then.

Some motherboards will be able to show VRM temps in HWInfo64, others you need an IR camera or temperature meter. HWInfo64 download link

Normal before delidding @ 5GHz 1.3 volts. Temps hit 99c on the cpu, Prime95 small fft's.
10k_temps_before-png.127894


Buildzoid I believe said that anything above 150Amps on the 9900k is uncoolable unless you delid. Here's an image of 200 Amps delidded (cpu 5GHz 271 watts):


this_will_keep_me_warm-png.127911

source

Note after delidding temps are fine in Prime95 small fft's @5GHz (they are in the low 90c's, maximum 94c). Note the power the cpu is pulling is 271 watts and the motherboard VRM are at 201 Amps @ 95c.
 
PSU will get the job done, its not an issue.

Really? Do you have some insider information that magically tells you exactly WHAT 750w power supply they have, or are you just assuming that because it's "750w" then it must be sufficient? This kind of blanket statement often ends up doing a lot of ass biting later. Not to bash your response, but that particular one wasn't particularly recommendable unless there's something I'm missing and I don't think there is. If the OP has determined they need to replace the PSU then it's probably because they've determined that what they have has quality issues, not capacity issues.
 
These are the temps @ 150 Amps delidded. See that even in Prime95 small fft's you can get under 90c with a 5GHz 9900k
Running at >85°C consistently, on a regular basis, even intermittently for long periods of time, is probably not the greatest idea. If you have to do that, then you would be wise to reduce something somewhere. Electromigration and VT shift are going to start having a long term effect on transistor performance.

So if that's how you need to NOT get there, then that's great, but keep in mind that if you don't REALLY know what you are doing, delidding can mean INSTANT death to your CPU, no medium to long term usage required. LOL.
 

Jnelly99

Commendable
Nov 30, 2019
21
0
1,510
Running at >85°C consistently, on a regular basis, even intermittently for long periods of time, is probably not the greatest idea. If you have to do that, then you would be wise to reduce something somewhere. Electromigration and VT shift are going to start having a long term effect on transistor performance.

So if that's how you need to NOT get there, then that's great, but keep in mind that if you don't REALLY know what you are doing, delidding can mean INSTANT death to your CPU, no medium to long term usage required. LOL.
So would delidding be worth it? I dont want my cpu running at 90 degrees all the time im fine with doing like 4.8 or 4.9 and having it under 90 degrees then 5ghz and have 90degrees all the time. I have never delidded before but have watched videos, maybe not worth it right now on my current cpu as its the only one i have and would rather not destroy it untill the new cpu's come out this year.
 

zx128k

Reputable
Really? Do you have some insider information that magically tells you exactly WHAT 750w power supply they have, or are you just assuming that because it's "750w" then it must be sufficient? This kind of blanket statement often ends up doing a lot of ass biting later. Not to bash your response, but that particular one wasn't particularly recommendable unless there's something I'm missing and I don't think there is. If the OP has determined they need to replace the PSU then it's probably because they've determined that what they have has quality issues, not capacity issues.

I have already posted the information you need above. He can't cool the 9900k if the cpu is above 150A, so his cpu will pull approx. 200Watts or so when overclocked. With the GPU at maximum 280 watts and pump 22-35 watts maximum. He should have enough power left. See the psu tier list I posted the PSU is teir 1. It's a decent PSU. S teir PSU are much more expensive.

Personaly I would get a higher watt PSU and go with a better 80 rating like platinum or titanium. I have a AX1000 Titanium but I never cut costs with the PSU. Even so he may get by fine with the 750 watt 80 gold PSU and limit amps for the 9900k to 150. Keep the overclock moderate, temps wise he may have no choice. This will limit power draw to a managable level for his PSU as well.

The 9900k runs that hot in prime95 small fft's. There is no way to avoid it because of the power draw at higher frequencies like 5GHz. Delidding and going direct die yelds lower temps in games and prime95. At a certain point, to be able to cool the 9900k you have no choice.

Nn4U4lg.png

Image 1: Got a Corsair H115i AIO 280mm, OC'ed 9900k @5GHz. Great is it stable? Run aida64, first stop 100c on every core.

You're right about delidding, failure can damage the cpu beyond repair (you don't have to do something wrong, crap happens). Good luck RMA'ing that CPU.

The 9900k will run at higher temps like >85c all day long. The issue is that at higher frequencies you will go >90c and start hitting 100c. Hitting TJUNCTION 100°C is the point the cpu will start thermal throttling.

To fix it, you either have to limit the power draw of the cpu, reduce the frequency (AVX offset that keeps the CPU at 4.7-4.8GHz), reduce the vcore or take action to improve cooling. A chiller (expensive) is one example of pushing the limits cooling wise. Some people buy the MORA3 Radiator https://thermalbench.com/2016/09/12/watercool-heatkiller-mo-ra3-420-pro-radiator/2/.

 

zx128k

Reputable
So would delidding be worth it? I dont want my cpu running at 90 degrees all the time im fine with doing like 4.8 or 4.9 and having it under 90 degrees then 5ghz and have 90degrees all the time. I have never delidded before but have watched videos, maybe not worth it right now on my current cpu as its the only one i have and would rather not destroy it untill the new cpu's come out this year.

It won't and you can use an AVX offset etc to keep temps under control without delidding. Or limit the amps the cpu can pull and thus limit Temps. There will be a performance loss.

You can pay to have a 9900k delided and laped. Even so you can still crack the die if you go with direct die cooling and fail at mounting the water block or use too much pressure.
 

Jnelly99

Commendable
Nov 30, 2019
21
0
1,510
It won't and you can use an AVX offset etc to keep temps under control without delidding. Or limit the amps the cpu can pull and thus limit Temps. There will be a performance loss.

You can pay to have a 9900k delided and laped. Even so you can still crack the die if you go with direct die cooling and fail at mounting the water block or use too much pressure.
I figured it wouldn't be worth it, i think i will just go with a off set on the cpu instead, i dont do much besides game on my pc and stream once in awhile so im not stressing the pc that hard. I will be getting a higher watt psu tho just incase. Hoping i can cancel my cable mod cables now tho lol.
 

zx128k

Reputable
I figured it wouldn't be worth it, i think i will just go with a off set on the cpu instead, i dont do much besides game on my pc and stream once in awhile so im not stressing the pc that hard. I will be getting a higher watt psu tho just incase. Hoping i can cancel my cable mod cables now tho lol.

Delidding the cpu does not cost much if you buy a cpu thats already delidded for you. Example https://www.overclockers.co.uk/inte...ket-lga1151-processor-oem-cp-00f-8p.html#t=a2

If you want to replace the PSU thats up to you.

The video shows an example of were in the bios you would limit the CPU power. Note most games won't cause the cpu to run at its maximum power draw. So you are just limiting power for the heaviest of loads. This way you never have to worry about what avx loads you run. This will keep you from hitting 100c in prime95, aida64 or HEVC etc. There is an option to change the core curent limit. From what I have read 150 amps sames like a good limit but you can play about with the settings. One to see if this is likely to work and to find what the best values are likely to be.


Max VID - (resistance * amps)= max safe live voltage, up to TJMAX.

That means at 150 amps, 1.340v set in BIOS and 0.4 mOhms of loadline calibration, you are right at the max safe limit, and should be very careful about raising vcore without improving your cooling solution. (in this example, pulling less than 150 amps puts you below the safe limit, pulling more than 150 amps starts to put you beyond it).
View: https://www.reddit.com/r/overclocking/comments/dso1b8/whats_the_max_safe_voltage_for_a_247_overclock/

Just for reference, if you are using a true "Flat" LLC (measured via VCC_SENSE)--VR VOUT is an accurate VCC_Sense measurement but VR VOUT does NOT show transient spikes or drops, and transients will increase with tigher loadline!, you should NOT exceed 1.28v set in BIOS unless you are under sub-ambient cooling and if you are attempting to run AVX prime95, you should NOT exceed 1.24v set in BIOS! That's because at 193 amps of current (8 core), max VCC_Sense voltage (with respect to ground), with 193 amps being absolute max allowed by Intel, is between 1.212v-1.230v (depending on where it's measured).

Maybe
Darkbreeze knows more, this is all I know or can find out.
 
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I have already posted the information you need above. He can't cool the 9900k if the cpu is above 150A, so his cpu will pull approx. 200Watts or so when overclocked. With the GPU at maximum 280 watts and pump 22-35 watts maximum. He should have enough power left. See the psu tier list I posted the PSU is teir 1. It's a decent PSU. S teir PSU are much more expensive.

Personaly I would get a higher watt PSU and go with a better 80 rating like platinum or titanium. I have a AX1000 Titanium but I never cut costs with the PSU. Even so he may get by fine with the 750 watt 80 gold PSU and limit amps for the 9900k to 150. Keep the overclock moderate, temps wise he may have no choice. This will limit power draw to a managable level for his PSU as well.

I was ONLY referring to the statement about his PSU being fine as is, without even knowing what PSU he actually has. What I WASN'T responding to in that reply was anything else you said, regarding the entire process or delidding or anything else.

As far as the PSU is concerned, the 80plus rating is irrelevant unless the platform is already known to be excellent AND is a model from a brand who has ensured a quality build using that platform. We sometimes see two different implementations of the same platform, and one is great while the other using the same platform is not so great. This is EXACTLY WHY always knowing the EXACT model is imperative before making any judgements regarding fitness for a particular use or probably reliability of a unit.

Just saying "You need to get a 1200w (Insert whatever wattage you want, there will certainly be similarly bad examples of it out there somewhere without even having to look hard for them) Titanium rated PSU" could lead to somebody buying any number of really terrible units such as this one, as just ONE example. And yes, there are similarly poor quality Gold and Platinum units out there as well.


 

zx128k

Reputable
I was ONLY referring to the statement about his PSU being fine as is, without even knowing what PSU he actually has. What I WASN'T responding to in that reply was anything else you said, regarding the entire process or delidding or anything else.

As far as the PSU is concerned, the 80plus rating is irrelevant unless the platform is already known to be excellent AND is a model from a brand who has ensured a quality build using that platform. We sometimes see two different implementations of the same platform, and one is great while the other using the same platform is not so great. This is EXACTLY WHY always knowing the EXACT model is imperative before making any judgements regarding fitness for a particular use or probably reliability of a unit.

Just saying "You need to get a 1200w (Insert whatever wattage you want, there will certainly be similarly bad examples of it out there somewhere without even having to look hard for them) Titanium rated PSU" could lead to somebody buying any number of really terrible units such as this one, as just ONE example. And yes, there are similarly poor quality Gold and Platinum units out there as well.



I started building PC's along time ago when you got a cheap PSU with the case. I had a number of PSU fires happen. One when a water pump in my coolance case went on fire and another with a Chinese 1000 w titanium PSU filled my server with smoke.

Then there is the strange issues you get with bad PSU's, as nothing you put in the case works right. That's why I buy the PSU that are in the s-teir in the PSU teir list. I got a Corsair AX1000 PSU based on reviews. https://www.tomshardware.com/uk/reviews/corsair-ax1000-80-plus-titanium,5966.html The PSU has low ripple.

The PSU teir list can be a good start to finding a decent PSU. https://www.tomshardware.com/uk/reviews/best-psus,4229.html I picked this link as it has a nice tldr list.

Best power supply units at a glance:

  1. Bitfenix BF450G
  2. Corsair RM550x <----- The OP PSU is a RM750x https://www.tomshardware.com/uk/reviews/corsair-rm750x-v2-psu,5585.html
  3. Seasonic SSR-600TL
  4. Seasonic SSR-750PX
  5. Corsair AX850
  6. Corsair AX1000 <----- This is my PSU.
  7. Corsair AX1600i
  8. Corsair SF750
 
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