# 12700K at 100C after few minutes of Prime95



## BlackAzrael (Jan 18, 2022)

12700K at 100C after few minutes of Prime95

Hello everyone,
Recently just got a CPU + Motherboard upgrade and got a Noctua NH-D15 CPU cooler to go with it.

Case Specs: http://nordic.thermaltake.com/products-model.aspx?id=C_00001719
Ran Prime95 and noticed the CPU goes to 100C within 3-5 minutes. I stopped the test immediately as it didn't seem normal. Now I'm kind of wondering if that's normal and checking if I should revise my fan setup for my case.
My current fans:
Noctua NF-P14s redux 1500rpm = 78.69 CFM (BACK EXHAUST)
Noctua NF-A15 x 2 (CPU Cooler) = 67.98 CFM  (EXHAUST directed towards back 140mm exhaust fan)
Noctua NF-A20 = 86.46 CFM (SIDE INTAKE)
Noctua NF-A20 = 86.46 CFM (TOP EXHAUST)
Noctua NF-F12 = 54.97 CFM  (BOTTOM INTAKE just under the GPU and besides PSU)
Thermaltake Pure 20 TT-2030 = 129 CFM (FRONT INTAKE, kind of doubtful if that's the true CFM)

Anyone have any suggestions on what to change or swap around?


Current system specs:
CPU: Intel 12700k
MOBO: MSI PRO-Z690A DDR4 Wifi
RAM: Corsair Vengeance LPX DDR4 2x8GB
GPU: Gigabyte 1080ti Aorus Xtreme
PSU: Thermaltake M850W
Case: Thermaltake Chaser MK-1


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## Fouquin (Jan 18, 2022)

Going off reports from others, it's likely not anything wrong with your cooling setup, but rather a problem with your motherboard. It may have physically bent under the load of installing the CPU and cooler, and now has uneven contact across the CPU.









						Cooling issues with Intel’s Alder Lake - Problems with the LGA-1700 socket and a possible workaround | igor'sLAB
					

Badly fitting coolers, too low performance with actually good waterblocks and bent CPUs – meanwhile not only the feedback of the readers is piling up, but also very similar reports from the board…




					www.igorslab.de


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## BlackAzrael (Jan 18, 2022)

Wow well that's shitty to say the least. I changed the motherboard + cpu literally just 2 days ago.

At least it's only when using Prime95, gaming and anything else (so far) seems totally fine as far as temps go.

I was thinking that I might have messed up on the thermal paste application.


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## Outback Bronze (Jan 18, 2022)

BlackAzrael said:


> gaming and anything else



What's your temps on these? Also what's your Ambient temps?


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## BlackAzrael (Jan 18, 2022)

Ambient temp is usually around 25C (24C to 26Cish) at least during winter.

Was testing some God of War and temps usually hover around 60c I think.


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## dark2099 (Jan 18, 2022)

Check the power limit settings in BIOS, @sneekypeet who uses a MSI board for testing RAM said it defaulted to giving his CPU 4096W of power, which could be why yours is running hot.

EDIT: Yes there might be an issue with mounting as I've seen reports of that too, JaysTwoCents did a video on how to fix the mounting issue. Also I realize if you're in the 60c range for gaming, and 100c when using Prime, you might be fine on everything, just Prime can cook a CPU.


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## ShiBDiB (Jan 18, 2022)

BlackAzrael said:


> temps usually hover around 60c I think.


sounds like you have nothing to worry about then imo. Prime isn't a really good example of real world conditions, it's more a stress test to make sure everything is stable. 

And I forgot how beefy those noctua's are... used to run one forever ago in an old build. I wouldn't touch them nowadays tho, ignoring the weight they're just big and ugly (and make doing anything in the case that much more annoying)


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## tabascosauz (Jan 18, 2022)

BlackAzrael said:


> Ambient temp is usually around 25C (24C to 26Cish) at least during winter.
> 
> Was testing some God of War and temps usually hover around 60c I think.



Not sure how CPU-demanding God of War is, but that sounds pretty good?

IIRC all-out AVX2 loads like default Prime95 small FFT will just run like an inferno on 11th and 12th gen. Aside from a small AVX offset (do they even do that anymore) I don't think Intel significantly throttles power usage during P95. The only reason Ryzen doesn't do the same is because AMD's boost algorithm is hardcoded to throttle insanely hard upon detecting small FFT AVX. AT tested the 12900K when it came out and it was also running balls-to-the-wall at 272W in their own AVX2 test, which I don't expect to be more demanding than P95 Small.

12700K is getting toward the upper end of what an air cooler on Alder Lake can realistically handle anyways. 

The socket bending issue shouldn't a problem for a brand-new system that was just assembled 2 days ago. The warping happens over time, and I'd expect your temperatures to be noticeably bad in other workloads as well such as games.


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## RJARRRPCGP (Jan 18, 2022)

I would hit the roof super hard, if that happened to me! 
Hopefully, it's not like the fiasco that some people apparently reported with the 3rd-gen Core i series, about 10 years ago now! Where people had to take the IHS off and change the TIM, if not running them delidded!



tabascosauz said:


> IIRC all-out AVX2 loads like default Prime95 small FFT will just run like an inferno on 11th and 12th gen. Aside from a small AVX offset (do they even do that anymore) I don't think Intel significantly throttles power usage during P95. The only reason Ryzen doesn't do the same is because AMD's boost algorithm is hardcoded to throttle insanely hard upon detecting small FFT AVX. AT tested the 12900K when it came out and it was also running balls-to-the-wall at 272W in their own AVX2 test, which I don't expect to be more demanding than P95 Small.


Some years ago, it looked like nothing could beat Linpack on Intel, period. Years ago, I would think that it would shut down with a Linpack load with the CPU in that kind of condition. 
I remembered when I couldn't ever get as high of core temps with Prime95, thus it felt like I was cheating to run Prime95, LOL! I know that small FFTs are by far the best for testing cores with Prime95, but I still don't know if it can hold a candle to Linpack, especially the recent versions. Sounds like Prime95 improved, but I guess I need to test that again. I'm actually scared to run Linpack on AMD CPUs, because of a problem where there are possibly false errors. Where I never saw Prime95 with large FFTs fail. But it should have failed if the RAM or bus was unstable!


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## chrcoluk (Jan 18, 2022)

60C seems warm for gaming in winter, under a noctua fan cooler my 9900k is usually between 40C and 50C.  maybe 55C in mid summer.


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## Space Lynx (Jan 18, 2022)

chrcoluk said:


> 60C seems warm for gaming in winter, under a noctua fan cooler my 9900k is usually between 40C and 50C.  maybe 55C in mid summer.



temps really depend on what kind of games you play and the monitor you use. i imagine if you played witcher 3 on max settings at 1440p high refresh, those temps would be more like 65-70 celsius


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## sneekypeet (Jan 18, 2022)

dark2099 said:


> @sneekypeet who uses a MSI board for testing RAM said it defaulted to giving his CPU 4096W of power



On my MAG Carbon Wifi, when you clear the CMOS and dive into the BIOS, there is a popup window that asks about cooling. Water is 4096W, aftermarket air is like 2000W, and only when you set it to boxed cooler does it set 241W as the cap. It may not be on all MSI boards though.


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## Deleted member 202104 (Jan 18, 2022)

sneekypeet said:


> On my MAG Carbon Wifi, when you clear the CMOS and dive into the BIOS, there is a popup window that asks about cooling. Water is 4096W, aftermarket air is like 2000W, and only when you set it to boxed cooler does it set 241W as the cap. It may not be on all MSI boards though.



Same behavior on a Z690 Pro-A WiFi DDR4


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## Erazor (Jan 19, 2022)

100C is too high. 

Can you run CPU Multicore bench on Cinebench R23 and report back on the temps?

Use HWiNFO to check your temps. 

I am also on a 12700k and Initially when I ran tests I was getting around 90C. I found out my motherboard had this feature called Multi-Core Enhancement (MCE) enabled. Disabling that and underclocking the CPU by 0.025v helped lower temps. Now I get low 80s while running Cinebench R23. Check your motherboard to see if you have something similar and disable as that increases the CPU voltage. 

My temps after completing multicore run on Cinebench R23.

CPU cooler I am using is SilentiumPC Fortis 5 Dual Fan.






						Fortis 5 Dual Fan : SilentiumPC
					






					www.silentiumpc.com


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## Deleted member 24505 (Jan 19, 2022)

weekendgeek said:


> Same behavior on a Z690 Pro-A WiFi DDR4



Really i haven't seen that in my bios, must have missed it.


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## ir_cow (Jan 19, 2022)

I'm not surprised by the 100C. I have to downclock to 4.2GHz for the Prime95 VRM tests just to keep it below 290 watts. Solution? Don't run Prime95 because it will pull 330+ if allowed.

If you don't thermal throttle with CineBench R20 after looping it for a bit, you are golden.


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## Deleted member 202104 (Jan 19, 2022)

Tigger said:


> Really i haven't seen that in my bios, must have missed it.



It's a MSI thing I believe. I saw it after the last BIOS update I did.  You have an ASUS, right?


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## Deleted member 24505 (Jan 19, 2022)

weekendgeek said:


> It's a MSI thing I believe. I saw it after the last BIOS update I did.  You have an ASUS, right?



Doh i misread the Z690 Pro-A WiFi DDR4 bit, mine Z690-A WiFi :s yes Asus


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## Deleted member 202104 (Jan 19, 2022)

Tigger said:


> Doh i misread the Z690 Pro-A WiFi DDR4 bit, mine Z690-A WiFi :s yes Asus



Totally get it - I had to check when I looked my post again and thought I had written Strix-A DDR4


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## Deleted member 24505 (Jan 19, 2022)

weekendgeek said:


> Totally get it - I had to check when I looked my post again and thought I had written Strix-A DDR4


I still very much like my Strix -A ddr4 board. Nice having 4xM.2. Z690 boards are pretty feature packed.


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## phanbuey (Jan 19, 2022)

Im super tempted to run a soft 2tb x 3 raid array for my gaming drive...  11 GB/s... give those efficiency cores stuff to do.


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## AlwaysHope (Jan 24, 2022)

sneekypeet said:


> On my MAG Carbon Wifi, when you clear the CMOS and dive into the BIOS, there is a popup window that asks about cooling. Water is 4096W, aftermarket air is like 2000W, and only when you set it to boxed cooler does it set 241W as the cap. It may not be on all MSI boards though.


It does that on my Z590 Unify too. But for tower air cooler the power cap is 288w, no where near 2000!


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## sneekypeet (Jan 24, 2022)

AlwaysHope said:


> It does that on my Z590 Unify too. But for tower air cooler the power cap is 288w, no where near 2000!


Could be a fluke. I am finding this board has other bios related issues, so at this stage, anything is possible.


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## AlwaysHope (Jan 24, 2022)

sneekypeet said:


> Could be a fluke. I am finding this board has other bios related issues, so at this stage, anything is possible.


Sounds a bit like my Z590 Gigabyte board to some extent. Not claiming its a bad board, but settings the user dials in did not stick when the OS booted up to the desktop.


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## markm75 (Aug 9, 2022)

Just curious for others like myself despite fixing limits that still hit 100c during prime95, what program did you end up using to ultimately determine if the cpu is stable in the long run as a result?


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## Outback Bronze (Aug 9, 2022)

markm75 said:


> Just curious for others like myself despite fixing limits that still hit 100c during prime95, what program did you end up using to ultimately determine if the cpu is stable in the long run as a result?



I use Asus Realbench. Haven't used Prime for years now.


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## freeagent (Aug 9, 2022)

I use Linpack Xtreme, I haven’t used prime in eons..


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## ShrimpBrime (Aug 9, 2022)

freeagent said:


> I use Linpack Xtreme, I haven’t used prime in eons..


Same. I like Intel Burn Test though. That before prime95. 

None of this simulates general to heavy usage though. I mean we can stress a cpu all day, doesn't mean it'll game 4 hours straight (not that I ever do that, but some people do).


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## Solid State Brain (Sep 4, 2022)

I'm probably too late, but I have a similar configuration with the same motherboard and CPU. The default load voltage on this motherboard is very high and easily causes thermal throttling and high power consumption in stress tests like Prime95. This is caused by a high "AC Loadline" which can be found under "CPU Lite Load" in Advanced CPU settings. Decreasing AC Loadline decreases the load voltage, while keeping voltage at low loads or idle mostly unaffected.


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## ThrashZone (Sep 4, 2022)

freeagent said:


> I use Linpack Xtreme, I haven’t used prime in eons..


Hi,
Yeah not sure why people recommend using p95 it's just a power virus.


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## freeagent (Sep 4, 2022)

ThrashZone said:


> Hi,
> Yeah not sure why people recommend using p95 it's just a power virus.



In a way, Linpack is too. In the sense that there is not much, if any other load out there like it, at least that I have come across. But you get something out of it, that's why I use it.


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## Solid State Brain (Sep 4, 2022)

It's probably not too good for thermal stressing since there are no other sustained loads like it, but Prime95 can be useful for making sure that CPU is truly stable during intense transient loads. Think your CPU is stable? Fire up Prime95 for a few seconds, and chances are that the PC will freeze if load voltages are insufficient.

If it does, you could then either increase load voltages or decrease the CPU current limit so that the CPU will downclock slightly during such intense loads and avoid locking up.


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## ir_cow (Sep 4, 2022)

ThrashZone said:


> Hi,
> Yeah not sure why people recommend using p95 it's just a power virus.


Prime95 is still the "ultimate" stability test. The issue with these newest Intel CPUs is that many AIOs can't handle it. Secondly, many waterblocks can't handle it lol. Basically unless you enforce PL1+PL2 = 250, it will easily hit 100c.

I'm in the mid 90s with a stock 12900K (1.15v) with a custom waterloop and the only way I can run prime95 so far with a overclock is to delid the CPU and use liquid metal. Thats exactly what I did with a 12700K.

So in short, dont run prime95 with the Intel 11th / 12th gen cpu.


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## ThrashZone (Sep 5, 2022)

Hi,
I just use blender opendata and call it a done deal


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## ir_cow (Sep 5, 2022)

ThrashZone said:


> Hi,
> I just use blender opendata and call it a done deal


Pretty much if you can loop Cinebench or Blender your are good for the CPU. Use Y-Cruncher for a memory+CPU combo and that's about all you need to do. Is it guaranteed a good overclock? No, but its pretty good.


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## tpu7887 (Sep 5, 2022)

The following is the best advice by far. That is, if a stable system with the lowest possible voltage is what you're after...

If you don't know already, find out which of your cores are weakest (using prime95 at a lower voltage and clock speed, one that doesn't raise temps above what your real world loads reach). Then, run Prime95 on those cores, adding load to the remaining cores so that your weak cores running Prime95 reach the maximum temperature they do in real-world scenarios. Whatever voltage is required to prevent errors, add an additional 0.02 to 0.03V to ensure stability.

edit: To add heat, google "CPU burn in", in the first result download the 20kB file, each instance is one thread. You can assign them to cores as needed using task manager

edit2: If you're using a high voltage, periodically re-check stability every few months (this goes for any method you choose to use)


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## ThrashZone (Sep 5, 2022)

ir_cow said:


> Pretty much if you can loop Cinebench or Blender your are good for the CPU. Use Y-Cruncher for a memory+CPU combo and that's about all you need to do. Is it guaranteed a good overclock? No, but its pretty good.


Hi,
For my use case it's fine


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## tpu7887 (Sep 5, 2022)

ThrashZone said:


> Hi,
> For my use case it's fine



Did you miss my post? Not interested in _guaranteed stability_?


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## freeagent (Sep 5, 2022)

ir_cow said:


> No, but its pretty good


Or close enough 

Passes everything except one thing? I just pretend the program doesn't exist, unless a bout of OCD strikes.


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## ThrashZone (Sep 5, 2022)

Hi,
Not crunching
Not folding anything besides laundry
Not mining
My benchmarks are just fine I run plenty and never had any stability issues stop me from running a benchmark
So if you think p95 is some sort of score board benchmark we will agree to disagree there because it's not so no point in using it.
But please feel free to use p95 I'll use what I want to.

By the way W1zard uses blender to 
Why because it's a realistic workload.


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## Mussels (Sep 5, 2022)

This sadly is what i've been trying to explain to people about how the current intel systems work

They flip flop between PL1 and PL2, and have issues sustaining multi threaded performance unless you have a lot of cooling - you get the performance, but unless you meet certain criteria (unlocked power settings and very high end cooling) you cant sustain it.


There are definitely workarounds, your main choices would be lower PL1 and PL2 limits so the cooler has a chance to dissipate heat before it saturates completely, or an all core overclock at more efficient settings

(Ex: my 5800x runs at 4.4 (all core) - 5.05 (1-2T) at 75C, but a static 4.6GHz runs at 50C)


Also since intel platforms often have AVX offsets, make sure you're testing with AVX and non AVX programs and both sets of clocks are stable.
There's no use only testing a system for non AVX workloads, since games are using them too - you're either going to get lower clocks and performance than you expect, or instability by ignoring it.


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## Solid State Brain (Sep 5, 2022)

ThrashZone said:


> By the way W1zard uses blender to
> Why because it's a realistic workload.



The problem is that Blender or Cinebench are not sufficiently intense stability tests. The CPU can be effectively stable with them but then fail within a few seconds (before thermal throttling is even reached) with Prime95 AVX2/SmallFFT, or also specialized MT workloads like Linux kernel compilation.

A CPU that can freeze at any moment depending on the software used cannot be really considered stable in my opinion. A solution to this however is making sure that the CPU cannot reach in the first place such unstable operating points, which could be done not only with increased voltages, but also with current - power - temperature limits. By lowering these limits, lower CPU voltages than normally possible can even be used, since the CPU will be more prone to throttling when pushed to the limit.

As a side note, the opening post was about high temperatures with Prime95 despite using a Noctua NH-D15, and one big reason for that are the high voltages that the MSI Z690-A Pro applies with default settings. Well, at least they will lead to stable CPU operation. That Noctua should be able to handle the thermal load without throttling up to about 200-210W, but it will not be silent.


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## ratirt (Sep 5, 2022)

damn a 100c with a noctua air cooler. Should it even get that high despite what workload it is? 100c is literally throttling and yet people say their Intel 12th gen CPU run cool and dont use a lot of power and yet you have these reports. 
Maybe limit the power to 125w for PL1 and PL2 would help since I clearly don't see any other choice. Unless you fiddle with the settings every now and then to make it stay cool enough.


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## ThrashZone (Sep 5, 2022)

Solid State Brain said:


> The problem is that Blender or Cinebench are not sufficiently intense stability tests. The CPU can be effectively stable with them but then fail within a few seconds (before thermal throttling is even reached) with Prime95 AVX2/SmallFFT, or also specialized MT workloads like Linux kernel compilation.
> 
> A CPU that can freeze at any moment depending on the software used cannot be really considered stable in my opinion. A solution to this however is making sure that the CPU cannot reach in the first place such unstable operating points, which could be done not only with increased voltages, but also with current - power - temperature limits. By lowering these limits, lower CPU voltages than normally possible can even be used, since the CPU will be more prone to throttling when pushed to the limit.
> 
> As a side note, the opening post was about high temperatures with Prime95 despite using a Noctua NH-D15, and one big reason for that are the high voltages that the MSI Z690-A Pro applies with default settings. Well, at least they will lead to stable CPU operation. That Noctua should be able to handle the thermal load without throttling up to about 200-210W, but it will not be silent.


Hi,
On the same note you can run p95 until hell freezes and bsod on BF5  
Again blender uses a realistic workload with avx content so gaming you're better off not worse off using it instead

Besides you can use blender opendata or demo rendering files for cpu and gpu testing so much better.
Blender Open Data — blender.org

Demo Files — blender.org


R15-R20-R23 are indeed silly testing loads, none use much of any avx content to trigger any offsets if used even looped
But one thing these three have in common is they are benchmarks and there are leader boards.


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## Solid State Brain (Sep 5, 2022)

ThrashZone said:


> Hi,
> On the same note you can run p95 until hell freezes and bsod on BF5



It also depends on how you're running Prime95. For instance, under thermal-throttled conditions you're not maximizing internal peak currents, just thermally stressing the CPU.




ThrashZone said:


> R15-R20-R23 are indeed silly testing loads, none use much of any avx content to trigger any offsets if used even looped
> But one thing these three have in common is they are benchmarks and there are leader boards.



Cinebench R23 causes about the same power draw as with Blender during rendering (which I use for many purposes, not just benchmarks or stress testing), I think it's about on par as for CPU load.




ratirt said:


> damn a 100c with a noctua air cooler.



I have about the same configuration as the OP, with same CPU-motherboard and Noctua cooler but one less fan (NH-D15*S*). At maximum fan speed it is able to dissipate about 200W keeping temperatures slightly below thermal throttling, with a 28C ambient temperature (it will of course work better in the winter). The dual-fan version might be able to fare slightly better. It's a good air cooler but it can't perform miracles.

EDIT: it's not that the cooler gets hot (it is only somewhat warm to the touch under such testing conditions), it has a limit to how quickly it can extract heat from the CPU.


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## tpu7887 (Sep 6, 2022)

Mussels said:


> This sadly is what i've been trying to explain to people about how the current intel systems work
> 
> They flip flop between PL1 and PL2, and have issues sustaining multi threaded performance unless you have a lot of cooling - you get the performance, but unless you meet certain criteria (unlocked power settings and very high end cooling) you cant sustain it.
> 
> ...



I like your method mixed with mine.


"If you don't know already, find out which of your cores are weakest (using prime95 at a lower voltage and clock speed, one that doesn't raise temps above what your real world loads reach). Then, run Prime95 on those cores, adding load to the remaining cores so that your weak cores running Prime95 reach the maximum temperature they do in real-world scenarios. Whatever voltage is required to prevent errors, add an additional 0.02 to 0.03V to ensure stability.

edit: To add heat, google "CPU burn in", in the first result download the 20kB file, each instance is one thread. You can assign them to cores as needed using task manager"



Then, set a CPU power limit in the BIOS at 3-5 watts over the amount reached during the above stability test (the power dissipated in the (usually) most demanding program). Then, if something out of the ordinary happens, your system doesn't hang! (the extra 0.02-0.03V easily allows for the extra 3-5 watts dissipation)


edit: like a lot of people I do think running P95 on all cores is a stupid way to ensure stability for systems that don't run loads anywhere near as demanding, but P95 applied as above should be the standard method


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## ratirt (Sep 6, 2022)

Solid State Brain said:


> It also depends on how you're running Prime95. For instance, under thermal-throttled conditions you're not maximizing internal peak currents, just thermally stressing the CPU.
> 
> 
> 
> ...


That is why it is weird. I got two TR 3970x's with the Noctual U15 (if I remember correctly) and I can run them at full load no problem and the temp never gets to a 100 and still it is a 32c CPU.  
OP got something wrongly mounted or thermal paste problem. Maybe air circulation in the chassis sucks so bad.


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## pavle (Sep 6, 2022)

tabascosauz said:


> Not sure how CPU-demanding God of War is, but that sounds pretty good?
> 
> IIRC all-out AVX2 loads like default Prime95 small FFT will just run like an inferno on 11th and 12th gen. Aside from a small AVX offset (do they even do that anymore) I don't think Intel significantly throttles power usage during P95. The only reason Ryzen doesn't do the same is because AMD's boost algorithm is hardcoded to throttle insanely hard upon detecting small FFT AVX. AT tested the 12900K when it came out and it was also running balls-to-the-wall at 272W in their own AVX2 test, which I don't expect to be more demanding than P95 Small.
> 
> ...


As the quoted poster said and I add: you're running a basically at least 200W CPU (at 100%) cooled by an air cooler. Of course it is going to get hot.


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## Solid State Brain (Sep 6, 2022)

ratirt said:


> That is why it is weird. I got two TR 3970x's with the Noctual U15 (if I remember correctly) and I can run them at full load no problem and the temp never gets to a 100 and still it is a 32c CPU.
> OP got something wrongly mounted or thermal paste problem. Maybe air circulation in the chassis sucks so bad.



The AMD Threadripper 3970X should have a significantly lower heat density and will be easier to cool for the same power than CPUs with smaller dies.

Furthermore, as I mentioned earlier, with default settings the same motherboard as the original poster overvolts the CPU and uses very high limits (288W / 512A after choosing "Tower Air Cooler" on the initial setup), and under such conditions with Prime95 AVX2 / Small FFT power draw can easily go above 250W with the 12700K, at least while it is below the thermal throttling point.


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## ratirt (Sep 6, 2022)

Solid State Brain said:


> The AMD Threadripper 3970X should have a significantly lower heat density and will be easier to cool for the same power than CPUs with smaller dies.
> 
> Furthermore, as I mentioned earlier, with default settings the same motherboard as the original poster overvolts the CPU and uses very high limits (288W / 512A after choosing "Tower Air Cooler" on the initial setup), and under such conditions with Prime95 AVX2 / Small FFT power draw can easily go above 250W with the 12700K, at least while it is below the thermal throttling point.


With the die size sure. Smaller is harder to cool but 12700k is not a small one. 215mm2 is quire big in comparison to a 5800x which is 81mm2 and you can still cool it with any noctua cooler no problem. Even though there were some complaints about the 5800x being hot as hell which I could not see. Hotter than a 5900x for instance but overheating and hot as hell it was not.

Obviously, if you cooler can't manage, limit the processor till you feel comfortable using it.


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## Rob6502TPU (Sep 6, 2022)

ir_cow said:


> I'm not surprised by the 100C. I have to downclock to 4.2GHz for the Prime95 VRM tests just to keep it below 290 watts. Solution? Don't run Prime95 because it will pull 330+ if allowed.
> 
> If you don't thermal throttle with CineBench R20 after looping it for a bit, you are golden.


Come on this is a nonsense, Intel & Mobo vendors have together conspired to overclock by default for benchmark scores.
These CPUs are NOT throttling to TDP due to rotten tau settings and are NOT restricting to spec PL2.
This "run yer PC" gently is a result of shabby practices.  Developers are one slip away from creating runaway power hogs that can burn >300w and the tech press are letting Intel get away with this.
These boards/CPUs are defective not observing design specifications.


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## AM4isGOD (Sep 6, 2022)

ratirt said:


> yet people say their Intel 12th gen CPU run cool and dont use a lot of power



He was running prime 95, you think they use max power and run hot all the time? mine runs at 80c and uses 200 watts just idle on windows /s. of course it is going to run hot and use a lot of power running prime 95.


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## Solid State Brain (Sep 6, 2022)

Rob6502TPU said:


> Come on this is a nonsense, Intel & Mobo vendors have together conspired to overclock by default for benchmark scores.
> These CPUs are NOT throttling to TDP due to rotten tau settings and are NOT restricting to spec PL2.
> This "run yer PC" gently is a result of shabby practices.  Developers are one slip away from creating runaway power hogs that can burn >300w and the tech press are letting Intel get away with this.
> These boards/CPUs are defective not observing design specifications.




In reality there's no real 'spec' PL1/PL2/Tau, only Intel-defined _recommendations_. You (the system builder/integrator) are supposed to configure them according to your system capabilities and needs; they may be set higher than default/recommended if the system can support them. IccMax however (current limit) is part of the processor's electrical specifications and is not intended to be exceeded.

The problem is largely the defaults settings used by motherboard manufacturers, which assume (or pretend) that end users all have high-end water cooling systems and want performance no matter the cost (power consumption, temperatures, etc).

Images from the pdf version of the datasheet here: https://edc.intel.com/content/www/u...-1-of-2/001/processor-line-thermal-and-power/


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## ratirt (Sep 6, 2022)

AM4isGOD said:


> He was running prime 95, you think they use max power and run hot all the time? mine runs at 80c and uses 200 watts just idle on windows /s. of course it is going to run hot and use a lot of power running prime 95.


If it was Furmark I would not make a fuss around it but prime95 is ok for testing. If you get 100c on the CPU something is not ok. Not sure what you mean by run hot all the time? if you use it at 100% yeah it will be hot all the time and when you idle it wont. The problem is not to have a temp of a 100c when you have to use it despite time span while it is 100% utilized.


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## Vario (Sep 6, 2022)

Just don't run Prime95. If its <80C for your normal applications (games, software, etc) don't worry about it.


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## tpu7887 (Sep 6, 2022)

ratirt said:


> If it was Furmark I would not make a fuss around it but prime95 is ok for testing. If you get 100c on the CPU something is not ok. Not sure what you mean by run hot all the time? if you use it at 100% yeah it will be hot all the time and when you idle it wont. The problem is not to have a temp of a 100c when you have to use it despite time span while it is 100% utilized.



It seems my posts on prime95 have been missed or overlooked or skimmed by many. The reason people aren't using P95 is because it requires more power than all of their real world loads, and by a large margin. Problem is, none of the programs they're using to check for stability are thoroughly checking for errors. Below is how to overclock with the lowest voltage while ensuring error free operation (which, correct me if I'm wrong here... is what we all want).


Most demanding programs people run (like games) only make CPUs draw 50-70% of the amount of power that prime95 does. A CPU running at 5GHz with 1.3V can run perfectly fine at 80 degrees, but at 95 be throwing errors left and right- 1.34V might be required for proper operation at 95. But then 1.355V is required for temps which are 99 at 1.34, making 1.365V what's actually required. And you're then at 100, thermal throttling.
If none of the real world loads _ever _demand power levels as high as P95 small FFT on all cores, 1.35V isn't needed for stability, just 1.3V.

I laid out an easy method to tune to the optimal hypothetical 1.3V using Prime95. Once that's done, the CPU can be power limited so that it never reaches over 80 deg C during operation, and all is good! It will run just as error free in all applications, as if you tested Prime 95 on all cores at once, requiring much less voltage or allowing higher frequencies (take your pick on which you'd like). Caveat: only up to the power levels that normal loads demand of the CPU (which is not a problem because you tuned the power to the real world maximum...)

edit: I put the (very) easy method below for reference. You do with P95 the same as you would if running on all cores. 90-180 minutes coarse adjustments, 30+ hours on the final run



tpu7887 said:


> If you don't know already, find out which of your cores are weakest (using prime95 at a lower voltage and clock speed, one that doesn't raise temps above what your real world loads reach). Then, run Prime95 on those cores, adding load to the remaining cores so that your weak cores running Prime95 reach the maximum temperature they do in real-world scenarios. Whatever voltage is required to prevent errors, add an additional 0.02 to 0.03V to ensure stability.
> 
> edit: To add heat, google "CPU burn in", in the first result download the 20kB file, each instance is one thread. You can assign them to cores as needed using task manager
> 
> edit2: If you're using a high voltage, periodically re-check stability every few months (this goes for any overclock)


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## Rob6502TPU (Sep 7, 2022)

Solid State Brain said:


> In reality there's no real 'spec' PL1/PL2/Tau, only Intel-defined _recommendations_. You (the system builder/integrator) are supposed to configure them according to your system capabilities and needs; they may be set higher than default/recommended if the system can support them. IccMax however (current limit) is part of the processor's electrical specifications and is not intended to be exceeded.
> 
> The problem is largely the defaults settings used by motherboard manufacturers, which assume (or pretend) that end users all have high-end water cooling systems and want performance no matter the cost (power consumption, temperatures, etc).
> 
> Images from the pdf version of the datasheet here: https://edc.intel.com/content/www/u...-1-of-2/001/processor-line-thermal-and-power/


Exactly Intel are allowing configurations which are running extremely hot and just turning a blind eye.  That means a race to the max power to "win" benchmarks.
The users should NOT have to worry about what defaults the mobo manufacturs use and let's be clear.  INTEL IS AT FAULT HERE.
The processors I see are advertised at far lower TDP than they would actually be run at.


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## ir_cow (Sep 7, 2022)

Rob6502TPU said:


> Come on this is a nonsense, Intel & Mobo vendors have together conspired to overclock by default for benchmark scores.
> These CPUs are NOT throttling to TDP due to rotten tau settings and are NOT restricting to spec PL2.
> This "run yer PC" gently is a result of shabby practices.  Developers are one slip away from creating runaway power hogs that can burn >300w and the tech press are letting Intel get away with this.
> These boards/CPUs are defective not observing design specifications.


No they are not defective,  Intel is to blame for marketing the CPUs with lower TPD than they really have. If Intel really cared they would have enforced a lower power target. Every Z690 I've come across so far automatically sets P1+P2 = to 4096. Anyway you slice it. If you have a 12900K, it will pull 241 watts in Cinebench, Blender, etc. Motherboards have a option to allow the CPU to boost higher, thus more power. Using P1+P2= 4096 doesn't mean it will draw that much, just means the motherboard is no longer limiting the power load requested by the CPU.


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## phanbuey (Sep 7, 2022)

Rob6502TPU said:


> Exactly Intel are allowing configurations which are running extremely hot and just turning a blind eye.  That means a race to the max power to "win" benchmarks.
> The users should NOT have to worry about what defaults the mobo manufacturs use and let's be clear.  INTEL IS AT FAULT HERE.
> The processors I see are advertised at far lower TDP than they would actually be run at.



This is true for the K series as a whole, kind of the whole point of the K series is unlocked everything.  If you let your motherboard set everything unlocked, the chip will run hot when you run prime 95 . Not seeing the issue or fault here.

You don't see these threads with non-K CPUs for this reason.  Intel locks these parts down and sells them cheaper with non-K branding that run at the at lower TDP within 5-10% of the performance of the K skus.

This has been true since the pentium EE days. Core xtreme or whatever they called it - all the unlocked K chips run hot AF even back down to ivy bridge.


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## Rob6502TPU (Sep 7, 2022)

phanbuey said:


> This is true for the K series as a whole, kind of the whole point of the K series is unlocked everything.  If you let your motherboard set everything unlocked, the chip will run hot when you run prime 95 . Not seeing the issue or fault here.
> 
> You don't see these threads with non-K CPUs for this reason.  Intel locks these parts down and sells them cheaper with non-K branding that run at the at lower TDP within 5-10% of the performance of the K skus.
> 
> This has been true since the pentium EE days. Core xtreme or whatever they called it - all the unlocked chips run hot AF even back down to sandy/ivy bridge.


Unlocked is different from arriving with stupid settings.  You should be able to increase power, alter tau.  If you do that you can be ready for thermals.


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## phanbuey (Sep 7, 2022)

Rob6502TPU said:


> Unlocked is different from arriving with stupid settings.  You should be able to increase power, alter tau.  If you do that you can be ready for thermals.



I get that -- they definitely could have had a more optimized setting between 288W and 125W.  100C is scary looking but within the safe limits of the chip - but:





I think we can all safely agree they missed the boat here a bit with the 51W for an extra 2.1% performance.


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## ir_cow (Sep 7, 2022)

The 12900KS has a Tj.Max of 115C. Same chip. 100c is looking to be a bit more safe 

I agree Intel should have just gone with 190W instead. Enforce it by default and the user has to change it in the BIOS. Oh well , next time I guess.


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## Solid State Brain (Sep 7, 2022)

ir_cow said:


> The 12900KS has a Tj.Max of 115C. Same chip. 100c is looking to be a bit more safe



Unclear where this information came from. On the Intel ark website it is listed at 90 °C and the datasheet mentions that the thermal control circuit (TCC) activation temperature (i.e. thermal throttling) by default is at 90 °C. It can be manually configured up to 115 °C, though.









						Product Specifications
					

quick reference guide including specifications, features, pricing, compatibility, design documentation, ordering codes, spec codes and more.




					ark.intel.com
				










			https://cdrdv2.intel.com/v1/dl/getcontent/655258


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## ir_cow (Sep 7, 2022)

@Solid State Brain It comes from the TPU 12900KS review. Every MB I've tested has the default at 100c for the 12900K (none S). Expect one, which was the ASrock ITX. That was 115c and it shouldn't have been.









						Intel Core i9-12900KS Review - The Best Just Got Better
					

The Intel Core i9-12900KS is the company's new flagship Alder Lake processor. After our review, we can confirm that it is the "world's fastest gaming CPU," but that comes at a price not only in terms of dollars, but increased power draw and heat output, too.




					www.techpowerup.com
				





> That's why my approach was a bit different from the usual for the best overclock. For the 12900KS, I started with all cores set to the same x49 multiplier for 4.9 GHz all-core and increased the voltage until I got close to the thermal limit of 115°C when running Prime95. Unlike other Alder Lake processors, including the Core i9-12900K, the KS has its out-of-the-box default thermal limit set to 115°C, not 100°C. 115°C is the highest manual setting you can pick in the BIOS for all Alder Lake CPUs. Since this is the default setting, Intel's warranty will cover operating the processor at up to 115°C, which is a good hint for users of other Alder Lake processors based on the same silicon; there's no reason those can't withstand 115°C, too.



Edit: TJunction and T.J Max are not the same thing.


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## Solid State Brain (Sep 7, 2022)

I mean, what is the source for this information from the TPU review (edit: suggesting that 115°C is the default for the 12900KS)? Public data from Intel appears to suggest that the default TjMax for the 12900KS is actually lower than other CPUs in the Alder Lake lineup, which could possibly be beneficial for stability. This could have been a BIOS bug or mishap—again, motherboard defaults shouldn't be trusted to represent what Intel actually recommends.



ir_cow said:


> Edit: TJunction and T.J Max are not the same thing.



The Ark website shows this by clicking on the [?] icon. It's referring to Tjunction as a maximum allowed temperature:


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## ir_cow (Sep 7, 2022)

@Solid State Brain. If the warranty covers 115c, than it isn't a bug.


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## Solid State Brain (Sep 7, 2022)

On my MSI Z690 motherboard an ominous message appears if I set the temperature limit above 105 °C. It doesn't inspire much confidence on 115 °C being a safe continuous limit. It is also counterintuitive that the more power-hungry i9-12900KS based on the same silicon would be fine at higher temperatures:


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## ratirt (Sep 8, 2022)

Solid State Brain said:


> On my MSI Z690 motherboard an ominous message appears if I set the temperature limit above 105 °C. It doesn't inspire much confidence on 115 °C being a safe continuous limit. It is also counterintuitive that the more power-hungry i9-12900KS based on the same silicon would be fine at higher temperatures:
> 
> View attachment 260969


100c is a lot. I would never have gone above that and to be fair I would have done whatever possible to drop the temp at least to 90c. 
There must be some misunderstanding. I doubt it can withstand 115c long term without damage.


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## mclaren85 (Sep 8, 2022)

Dictating not to run Primetest95 is not a valid suggestion. Primetest is one of the best softwares to emulate render performance. What if the op is a heavy premiere pro or topaz video enhance user?


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## Solid State Brain (Sep 8, 2022)

ratirt said:


> 100c is a lot. I would never have gone above that and to be fair I would have done whatever possible to drop the temp at least to 90c.
> There must be some misunderstanding. I doubt it can withstand 115c long term without damage.



The setting has a range of 90–115 °C, but the effective range can be different depending on whether a temperature offset is present, and I believe that on B-series motherboards it cannot be configured. On my system I've set it to 90 °C given that the 12900KS is supposed to have it at the same temperature according to Intel data. Techpowerup appears to be the only source suggesting 115 °C.

A lower temperature limit also means that the CPU will draw less power on sustained heavy loads with high PL2, although Intel suggests that it is not intended to be used as a means to maintain the TDP / PL1.

It's unfortunate that the temperature of the heat spreader (Tcase) cannot be directly monitored, since it is the CPU temperature that actually has a maximum specification in the same datasheets (59–71 °C depending on the model, and guess what: the 12900KS is on the lower end of this). On my motherboard there is "socket temperature" which I think might be a good approximation for that. If that is a good assumption, that temperature has a certain thermal inertia and the default 56s Tau makes a lot of sense with it. With a high ambient temperature (30 °C) at moderate fan speeds it also appears that the limit can be sustained only at a reasonable PL1 (e.g. 125W). In other words, I have doubts that sustained usage at a high PL2, even if core temperature is below TJmax, is actually truly within specifications.


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## ShrimpBrime (Sep 8, 2022)

Solid State Brain said:


> the temperature of the heat spreader (Tcase) cannot be directly monitored,


That's it right there. 

Software is made aware through algorithm, unless a direct reading is used otherwise, CoreTemp generally the most accurate in my opinion.  

But nothing beats a probe on an IHS plate. 

Tcase max should be awareness to the user that any throttling can happen at or beyond this temp point. 

If this where an AM4 AMD chip, the high temp alert is 70c - A default system with a core temp of 70c should command cpu fan 100% duty cycle. This can be changed up to only 75c by the user. (A lot of complaints on stock coolers of fans revving up). Thus the Tcase IS configurable of 5c on AMD systems. 

I always viewed the Tcase to be the "suggested" all core sustained load for long periods of time. This is more my opinion because it would never be stated in documentation in this fashion. 

Mind you I don't look at TDP as an energy usage, but more so as a thermal dissipation. If you think about 70c 

IE: 70c would be converted to roughly 239 BTU/hr. 

Maybe more of a challenge of how many thermals can you move in a short period of time rather than seeing if the CPU can hit it's thermtrip (typically around 110-115c) and be the golden winner of a burnt cpu.


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## Solid State Brain (Sep 8, 2022)

Here is a graphical representation of socket temperature on my motherboard during a Prime95 Load. On my CPU, PL1=125W, PL2=190W, Tau=56s , which is according to Intel recommendation. However, I set TJmax to 90 °C as I mentioned earlier.

With this setup and 29 °C ambient temperature, socket temperature initially ramps up relatively quickly (but not instantly) to a certain level while core temperature is pegged at 89–90°C. After the time at PL2 is exhausted (with a 56s Tau), socket temperature slightly backs down, then starts increasing slowly again. In other tests I observed that on the long term this levels off at about 61 °C.

If socket temperature can be assumed to be similar to case temperature/Tcase, short periods at TjMax should be fine for long-term reliability.

I honestly believe this is the way Intel intended these processors to be used.


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## Rob6502TPU (Sep 10, 2022)

phanbuey said:


> I get that -- they definitely could have had a more optimized setting between 288W and 125W.  100C is scary looking but within the safe limits of the chip - but:
> 
> I think we can all safely agree they missed the boat here a bit with the 51W for an extra 2.1% performance.


Absolutely you get it.  Most 12th gen purchasers though see a benchmark "win" and claim it's efficient using less power in normal use.  Effectively they ignore that constanty heavily loading these processors with mobo settings as delivered will probably end badly and that more power is used  than necessary even when loaded lighter.  Chips & Cheese article found the "race to idle" being efficient proved to be total BS



Solid State Brain said:


> Here is a graphical representation of socket temperature on my motherboard during a Prime95 Load. On my CPU, PL1=125W, PL2=190W, Tau=56s , which is according to Intel recommendation. However, I set TJmax to 90 °C as I mentioned earlier.





Solid State Brain said:


> ..
> If socket temperature can be assumed to be similar to case temperature/Tcase, short periods at TjMax should be fine for long-term reliability.
> 
> I honestly believe this is the way Intel intended these processors to be used.


A more plausible explanation is that E cores were intended originally to run efficiently for background tasks.
Then the Golden Cove cores bloated in the effort to beat Zen in ST, which meant they could not use more P cores, so E cores were used for the cache light creator type software dominating MT benchmarks used by reviewers.  That had the side effect of making AVX512 problematic.
Then what happened is the marketing people whacked up power limits to achieve the imperative benchmarking goal, ignored TDP so the i9 12900k could match Zen3 16c in the benchmarks.
In companies with Zen3 & ADL OEM built PCs used by developers, the ADL ones suffer instability through over heating.

They've pushed the responsibility onto motherboard makers, SIs and OEMs; the 51% power increase for 2.1% performance is NOT something a competent CPU designer would intend.
You're kidding yourself, if you hit a problem all the responsibility is on you for buying an unlocked CPU and not managing thermals better.


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## cadaveca (Sep 10, 2022)

Rob6502TPU said:


> the 51% power increase for 2.1% performance is NOT something a competent CPU designer would intend.


Actually, given how silicon works, it IS something that is planned for. That reading, for example, of 51% for 2.1% performance, is for that chip only. Another chip of the same type and model may only increase power use by 25% under the same workload due to having better silicon quality.

So not directly intend, but planned for, for sure, since this is inherent in how silicon chips work.


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## Solid State Brain (Sep 10, 2022)

Rob6502TPU said:


> A more plausible explanation is that E cores were intended originally to run efficiently for background tasks.
> Then the Golden Cove cores bloated in the effort to beat Zen in ST, which meant they could not use more P cores, so E cores were used for the cache light creator type software dominating MT benchmarks used by reviewers.  That had the side effect of making AVX512 problematic.
> Then what happened is the marketing people whacked up power limits to achieve the imperative benchmarking goal, ignored TDP so the i9 12900k could match Zen3 16c in the benchmarks.
> In companies with Zen3 & ADL OEM built PCs used by developers, the ADL ones suffer instability through over heating.
> ...



I only meant that running the CPU a high PL2 for periods in the order of a minute or so and then keeping it at a relatively low PL1 for the rest of the computation time makes sense if the intended aim is taking advantage of the "_available thermal capacitance_". From the datasheet linked earlier:





Clearly, they're not referring about core temperature, since it has almost no thermal inertia and reacts immediately to load changes. On the other hand, externally-measured temperatures very close to the CPU itself (e.g. socket temperature as I showed in the image posted the other day) react with speed consistent with the Intel-recommended Tau time.

Of course one might argue that the 240+ watts is an excessively high power draw, even if for short periods. That is a related but different subject.


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## agent_x007 (Sep 10, 2022)

Just offset VCore by -0,05V or -0,1V and check stability.
Decrease all boost frequencies by 100MHz, if it's not stable.


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## tpu7887 (Sep 13, 2022)

Solid State Brain said:


> I only meant that running the CPU a high PL2 for periods in the order of a minute or so and then keeping it at a relatively low PL1 for the rest of the computation time makes sense if the intended aim is taking advantage of the "_available thermal capacitance_". From the datasheet linked earlier:
> 
> View attachment 261314
> 
> ...



Say the heatsink is 40 deg C at idle (~15W) and you put 125W to the CPU and the CPU temp went up to 80 deg C.

If the same heatsink (shortly after the CPU was loaded) is 50 deg C at idle (15W) and you put 125W to the CPU at that point, the CPU temp would increase to 90 deg C.

I'm just pointing out they could be talking about this thermal capacitance (I think they are)


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## Rob6502TPU (Sep 13, 2022)

Solid State Brain said:


> I only meant that running the CPU a high PL2 for periods in the order of a minute or so and then keeping it at a relatively low PL1 for the rest of the computation time makes sense if the intended aim is taking advantage of the "_available thermal capacitance_". From the datasheet linked earlier:
> 
> View attachment 261314
> 
> ...


I see, I assumed you knew that PL2 was allowed for the whole duration of the heavy load, which is why the 100C thermal limit is hit and maintained on well optimised software using the CPU to max.


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## Solid State Brain (Sep 13, 2022)

tpu7887 said:


> Say the heatsink is 40 deg C at idle (~15W) and you put 125W to the CPU and the CPU temp went up to 80 deg C.
> 
> If the same heatsink (shortly after the CPU was loaded) is 50 deg C at idle (15W) and you put 125W to the CPU at that point, the CPU temp would increase to 90 deg C.
> 
> I'm just pointing out they could be talking about this thermal capacitance (I think they are)



125W would be a load within the processor's stated TDP. If the cooler is only sufficient enough not to cause thermal throttling at the TDP (minimum requirement by Intel), it is virtually guaranteed that the CPU will hit almost immediately the thermal throttling point at a significantly higher load. Even on my Noctua D15S, when a load of say 200W is applied, reported core temperature jumps from ~40 °C to 90°C within 2-3 seconds and reaches the thermal throttling point soon after that.

Cooler temperature however rises much slower than core does. And IHS temperature (Tcase), which unlike core temperature is part of the thermal specifications for lidded CPUs, can be expected to be close that of the cooler near its base, perhaps at a heatpipe. For this, a Tau time of 28~56 seconds as recommended does make sense.

The thermal specifications don't say that the CPU cannot be at the throttling point during the limited time at PL2 (or anyway at a power greater than PL1/TDP), only that core temperatures should be below TJmax when the CPU is at TDP, and that TCase should be below specification values. So the thermal behavior I showed the other day seems acceptable and within specification, in my opinion.



Rob6502TPU said:


> I see, I assumed you knew that PL2 was allowed for the whole duration of the heavy load, which is why the 100C thermal limit is hit and maintained on well optimised software using the CPU to max.



PL2 has always been intended to be limited in duration in the datasheets, not to last for the entirety of the heavy load (a rendering job could last hours or days or more, that seems excessive at PL2).

Alder Lake launch slides did mention that PL1=PL2 brings the best CPU performance, but that doesn't seem to be an official recommendation. So, what to trust? Datasheets or marketing slides?


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## tpu7887 (Sep 13, 2022)

Solid State Brain said:


> 125W would be a load within the processor's stated TDP. If the cooler is only sufficient enough not to cause thermal throttling at the TDP (minimum requirement by Intel), it is virtually guaranteed that the CPU will hit almost immediately the thermal throttling point at a significantly higher load. Even on my Noctua D15S, when a load of say 200W is applied, reported core temperature jumps from ~40 °C to 90°C within 2-3 seconds and reaches the thermal throttling point soon after that.
> 
> Cooler temperature however rises much slower than core does. And IHS temperature (Tcase), which unlike core temperature is part of the thermal specifications for lidded CPUs, can be expected to be close that of the cooler near its base, perhaps at a heatpipe. For this, a Tau time of 28~56 seconds as recommended does make sense.
> 
> The thermal specifications don't say that the CPU cannot be at the throttling point during the limited time at PL2 (or anyway at a power greater than PL1/TDP), only that core temperatures should be below TJmax when the CPU is at TDP, and that TCase should be below specification values. So the thermal behavior I showed the other day seems acceptable and within specification, in my opinion.



I completely agree what you described is in spec.

My point wasn't 125W, my point was the action. Whether that be at 65W or 250W.

I do get why you take issue with me using 125W for the example though - I should've used a value over TDP.

Delta - the difference between two values.

Think of the delta between CPU temperature and heatsink temperature. For example, if 200W creates a 50 deg C temperature delta and the heatsink is cooled to a temperature of 40 deg C at idle, the second you apply 200W, the CPU temperature rises to 90 deg C.

Now think, with 200W, how fast does the heatsink rise in temperature with the fan at 100%? If it's 5 deg C per minute, you have 120 seconds until thermal throttling occurs. As long as so much power isn't added that the delta is 60 degrees (instantly causing the CPU to hit 100 degrees), the CPU is fine thermally - Turbo Boost 3.0 I believe is the one which dictates you can do anything to the CPU up to that point, up to anything that doesn't exceed maximum current obviously

Ideally you have a cooling solution which is able to keep up with any real world load you apply to the CPU so that you never run into thermal throttling.


Side note: For these huge powers that are being allowed lately, I don't think it's a good thing for chip longevity - thermal cycling causes growing and shrinking of the loaded parts of the die, which over time is bad for connections between parts


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## Solid State Brain (Sep 13, 2022)

What I'm implying above more in general is that when the Intel-recommended PL2 can even be more than 3 times the PL1/TDP value, thermal throttling should be expected when the CPU is boosting above the TDP, in particular if mated with a cooler of its TDP class.

For instance, the 65W (non-k) 12900 has a PL2 of 202W. The previous 65W 11900 had an even higher PL2 of 224W. The boxed coolers they came with couldn't possibly dissipate such power for more than a few instants—much shorter than their Tau time—and would certainly cause the CPU to operate at TJMax until the limited boosting period expires, while CPU power slowly decreases due to the throttling.

However, thermal throttling, when operating under standard settings (dynamic voltages/frequencies), isn't necessarily a critical condition. The CPU will typically very gradually decrease frequencies and voltage to prevent internal temperatures from exceeding the limit, with no perceivable stuttering behavior that perhaps might have used to occur in the past, which made people try to avoid it at all costs. I'm currently running my 12700K with a 90 °C limit (it's configurable within a limited range on Z motherboards), which causes it to thermally throttle earlier and more also with real-world workloads (Blender, etc). There are no practical drawbacks that I can see except obviously that on average frequencies under full load will be lower and decrease quicker.

Of course (again), under standard settings it can be argued that CPU longevity could be negatively affected with frequent intense thermal and power excursions. Constant operation at the thermal limit is definitely not recommended by Intel, but they seem to be ok with these CPUs operating at high power and die temperatures for short periods of time. We'll see in a few years if they will start dying earlier compared to their predecessors.


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## Lei (Sep 13, 2022)

markm75 said:


> Just curious for others like myself despite fixing limits that still hit 100c during prime95, what program did you end up using to ultimately determine if the cpu is stable in the long run as a result?


I use Argus monitor. It automatically turns the pc to sleep if cpu reaches a certain temp.
So I can peacefully take shower and leave the PC on. 

I have an exe file that sleeps the PC, argus runs it when it hits a high temp (instead of sending me an email lol)


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