[SOLVED] 12700K - TDP and PL2 settings

Hard_ware

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Intention to buy an Intel 12700K CPU and mainboard MSI Z690 tomahawk DDR4 Wifi.

The CPU power ist needed for around 1-2 days every other 14 days.
Otherwise it is very important for me to have a very, very quiet PC with fans barely noticible. Target is 700 rpm for silent wing 3 fans in case and Dark Rock 4.

  1. Idea: I wonder if PL2, PL1 and TDP can be reduced in Bios settings for MSI Z690 tomahawk board to around 100W to prevent draw spikes?
  2. Other Idea if idea 1 is not possible: Set a 12700 non K (normally PL2 of 180W and 56s) to TDP 65W and PL2 to 100W for these 56s?
 
PL1/PL2 should be configurable in bios
you could also setup power profile in windows, set max CPU clock to 99%, this will disable CPU turbo and cpu clock would be around 100MHz below base clock (so like 3.53GHz), that should be around 100watts on full load
 
PL1/PL2 should be configurable in bios
you could also setup power profile in windows, set max CPU clock to 99%, this will disable CPU turbo and cpu clock would be around 100MHz below base clock (so like 3.53GHz), that should be around 100watts on full load
 
Doing it in bios is possible but it's a hassle to switch it back and forth.
You can use throttle stop in windows to set PL and TDP or intel extreme tuning utility to set up a low and quiet baseline and then high tdp profiles for whatever software needs the power.

Also if you are not running anything demanding the rest of the time it will not use a lot of power in the first place so maybe there will not even be a need to do any of this.
 

Hard_ware

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PL1/PL2 should be configurable in bios
you could also setup power profile in windows, set max CPU clock to 99%, this will disable CPU turbo and cpu clock would be around 100MHz below base clock (so like 3.53GHz), that should be around 100watts on full load
Good idea: Maybe this alone would do the trick already - but if 99% will disable turbo, then I will also loose turbo for E-Cores? And e.g loose turbo for P Cores in cases only 1-4 P Cores are needed?
 

Hard_ware

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Doing it in bios is possible but it's a hassle to switch it back and forth.
You can use throttle stop in windows to set PL and TDP or intel extreme tuning utility to set up a low and quiet baseline and then high tdp profiles for whatever software needs the power.

Also if you are not running anything demanding the rest of the time it will not use a lot of power in the first place so maybe there will not even be a need to do any of this.
You might be right, but just in case the fans will be too unstable because of short spikes, the fans will annoy me - I am looking for a solution ahead :)
 

Karadjgne

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There's 2 different cpus, with 2 power profiles.
The 12700K uses PL1 125w and PL2 of 190w for 56 seconds on opening an app or a new command.
The 12700 uses a PL1 of 65w and PL2 of 180w for 28 seconds on open an app or new command.

For silence, I'd use the 12700 and a 280mm/360mm AIO.
Reason for this is liquid coolers don't require ramping up fans like aircooling does with temp changes. You'd have plenty of capacity where a static fan curve will just work as is and not ramp for that first 28 seconds. Temps will fluctuate, but that's not really a concern with that level of cooling capacity.

You could also use a large capacity air cooler such as a Noctua NH-D15 or beQuiet DarkRock Pro4 and set fan curve restrictions for max fan speeds.

But either way, overboard cooling is required to drop fan speeds low enough to be next to silent.
 

Hard_ware

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For silence, I'd use the 12700 and a 280mm/360mm AIO.
Reason for this is liquid coolers don't require ramping up fans like aircooling does with temp changes. You'd have plenty of capacity where a static fan curve will just work as is and not ramp for that first 28 seconds. Temps will fluctuate, but that's not really a concern with that level of cooling capacity.

You could also use a large capacity air cooler such as a Noctua NH-D15 or beQuiet DarkRock Pro4 and set fan curve restrictions for max fan speeds.
Thanks for your ideas.
I didn´t take AIO coolers into account because they tend to be quite a bit louder than a good air cooler which operates (Dark Rock 4 only 21.4 db(A) max)
Your idea to just restrict the fan curve for max fan speeds should do it in case the cooling of the Dark Rock 4 is not sufficient to prevent ramping up the fans to high!
This will be my fallback solution and the CPU has to throttle in this case for my ears :)

Just for your Info: On most z690 boards TDP and PL2 will be handled as TDP=PL2, meaning, if this is not changed in bios the 12700k and 12900k might draw 190W/241W all the time when under 100% of load.
That is exactly what I would like to prevent because one does not get a lot of more benchmarks points comparing e.g. 12700K at 125W vs 190W.
 

Karadjgne

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Just for your Info: On most z690 boards TDP and PL2 will be handled as TDP=PL2, meaning, if this is not changed in bios the 12700k and 12900k might draw 190W/241W all the time when under 100% of load.
That is exactly what I would like to prevent because one does not get a lot of more benchmarks points comparing e.g. 12700K at 125W vs 190W.
Depends on the mobo and settings. Most bios has a factory default Standard power profile, and an Enhanced or Performance setting (some also have an Eco profile). Standard should follow Intel guidelines, but the Performance profile can bump to a max of 1000A and Tau of 99999 seconds, basically setting an unlimited and permanent PL2 profile, never getting drop to PL1.

TDP for all intents and purposes is PL1, not PL2.

If looking at a Z690 mobo + K, you could also overclock. Simply setting max turbo multiplier to equal base speeds. That'll limit performance cores to PL1 and not mess with the eco cores.

AIO's being louder than aircooling is an ancient idea and current fallacy. It originated with the original Corsair H series, which used miserable SP-120 fans, which were quite loud, whether on an aio, an air cooler or in a case.

Fans make noise, no getting around that. Whether that's blowing through a heatsink or a radiator makes no difference, the noise will be the same, depending on the fan. It was an opinion exasperated by constant comparison of the H100 vs NH-D14, which while similar in performance, were miles apart in noise output.

The DRP4 is 2db(A) quieter under a load than 6 different AIO's, and humans can't differentiate that small amount of decibels. Those AIO's are also quieter than the Noctua NH-D15/S coolers. (guru3d.com review)
 

Hard_ware

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Depends on the mobo and settings. Most bios has a factory default Standard power profile, and an Enhanced or Performance setting (some also have an Eco profile). Standard should follow Intel guidelines, but the Performance profile can bump to a max of 1000A and Tau of 99999 seconds, basically setting an unlimited and permanent PL2 profile, never getting drop to PL1.

TDP for all intents and purposes is PL1, not PL2.

If looking at a Z690 mobo + K, you could also overclock. Simply setting max turbo multiplier to equal base speeds. That'll limit performance cores to PL1 and not mess with the eco cores.

AIO's being louder than aircooling is an ancient idea and current fallacy. It originated with the original Corsair H series, which used miserable SP-120 fans, which were quite loud, whether on an aio, an air cooler or in a case.

Fans make noise, no getting around that. Whether that's blowing through a heatsink or a radiator makes no difference, the noise will be the same, depending on the fan. It was an opinion exasperated by constant comparison of the H100 vs NH-D14, which while similar in performance, were miles apart in noise output.

The DRP4 is 2db(A) quieter under a load than 6 different AIO's, and humans can't differentiate that small amount of decibels. Those AIO's are also quieter than the Noctua NH-D15/S coolers. (guru3d.com review)
Thank you very much for the info:
I fully agree with your considerations: As I see, good AIOs have only 2 to 3 db(A) more than the Dark Rock 4 under full load: Remark: 3 dbs is around 50% louder for ears.
Nevertheless: If I set a max rpm limit of the Dark Rock 4 to around 50% rpm it is definitely almost not noticible - maybe around 10 dba less than under full load - and there comes the advantage of air cooler over AIOs which are much louder at around 50% load - I think. But I have to admit I have no experience about AIOs under 50% load. If am not right I might change my configuration :)

Concerning PL1 and PL2:
You wrote "Simply setting max turbo multiplier to equal base speeds. That'll limit performance cores to PL1". Are you sure. My understanding is that if you overclock and want to have PL1 at 125W you also need to set PL2 at 125W. Because most mobos will set PL1=PL2 in overclock mode which would be 190W for 12700K and 241W for 12900K all the time. Am I correct here?

Oh, ok, I see what you meant: If I "disable" turbo to all P Cores I will have around 125W power draw? But then I loose turbo for all P Cores in cases in which total power draw is less than 125W e.g. applications needing 4 P Cores. 4 P Cores in turbo draw around 80W and would be much faster than if I set max turbo to base speed. One could loose quite a bit performance without need I think.
 

uWebb429

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@Hard_ware
Leave Intel Turbo Boost enabled. All Intel CPUs use turbo power limits which can be used to fully control how much heat these CPUs produce. You can adjust the power limits to whatever your cooling and your ears are comfortable with.

ThrottleStop 9.4.3

ThrottleStop gives you access to the Clamp options in the power limit register. Intel XTU does not have this feature and neither does the BIOS. Enabling both Clamp options guarantees that maximum power consumption is clamped to the values you have selected.

Here is an example of a 10850K that has been clamped to 65W. The CPU speed is automatically reduced as much as necessary so power consumption does not exceed 65W. If the Clamp option is not enabled, the CPU would only slow down to its base frequency which is 3600 MHz.



 
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Karadjgne

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Simply, there's 2 multipliers. The first, usually on the main page, is the cpu multiplier. That's going to be PL1. Most static OC will bump that up to where PL1 equals or exceeds current PL2, so if the multiplier is normally 46 and you move it to 50 for all cores, the cpu will stay at 5.0GHz. The second is turbo multiplier, which is down a tab or 2. That'll set the boost limits (PL2) but doesn't change the cpu multiplier. So if turbo for 1 core is 52, 2 cores 50, 3 cores 49 and 4 cores is 47 then for PL2 boost ranges depending on cores used those are the PL2 limits.

Change those to the same as the cpu multiplier and PL2 will be equal to PL1, instead of PL1 being equal to PL2. You'd see a turbo boost from 4.6GHz base, to 4.6GHz turbo etc. Turbo will still apply, and PL2 power draw will be the same as PL1 since there's no change in speeds, no extra power required to get the higher speeds etc.

And doesn't mess with the Ecores.

Trying to enforce power limits can create instability as the cpu tries in vain to reach its turbo limits, fails, and gets throttled to what the power allows. That can put you on a fine edge of where voltage is needed, demanded, and suddenly isn't there
 
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Hard_ware

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@Hard_ware
Leave Intel Turbo Boost enabled. All Intel CPUs use turbo power limits which can be used to fully control how much heat these CPUs produce. You can adjust the power limits to whatever your cooling and your ears are comfortable with.

ThrottleStop 9.4.3

ThrottleStop gives you access to the Clamp options in the power limit register. Intel XTU does not have this feature and neither does the BIOS. Enabling both Clamp options guarantees that maximum power consumption is clamped to the values you have selected.

Here is an example of a 10850K that has been clamped to 65W. The CPU speed is automatically reduced as much as necessary so power consumption does not exceed 65W. If the Clamp option is not enabled, the CPU would only slow down to its base frequency which is 3600 MHz.

Promising tool: I remember having used such a tool years ago for a notebook with annoying fans. I undervolted with the tool and limited the power - which did the trick.
In your picture section "Power Limit Control" is exactly what I think should or is in the Bios of Z690 mobos? Can anyone confirm this?
Normally PL1, PL" Power can be set in Bios? an for PL2 the duration for K CPUs? Am I right?

So, if e.g. I am able to set PL1 to 80W and PL2 to 100W for a duration of 10s - that would be my plan for a very quiet PC? Can these settings be done?
 

uWebb429

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Can these settings be done?
Try it and find out. Do some testing.

Most Z690 boards will give you access to PL1, PL2 and the turbo time limit in the bios but the bios will rarely if ever give you access to the Clamp options. That is the advantage of using ThrottleStop.

Your 80W and 100W settings will work just fine.
 

Hard_ware

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Simply, there's 2 multipliers. The first, usually on the main page, is the cpu multiplier. That's going to be PL1. Most static OC will bump that up to where PL1 equals or exceeds current PL2, so if the multiplier is normally 46 and you move it to 50 for all cores, the cpu will stay at 5.0GHz. The second is turbo multiplier, which is down a tab or 2. That'll set the boost limits (PL2) but doesn't change the cpu multiplier. So if turbo for 1 core is 52, 2 cores 50, 3 cores 49 and 4 cores is 47 then for PL2 boost ranges depending on cores used those are the PL2 limits.

Change those to the same as the cpu multiplier and PL2 will be equal to PL1, instead of PL1 being equal to PL2. You'd see a turbo boost from 4.6GHz base, to 4.6GHz turbo etc. Turbo will still apply, and PL2 power draw will be the same as PL1 since there's no change in speeds, no extra power required to get the higher speeds etc.

And doesn't mess with the Ecores.
If I understand your idea correctly, they are good for overclocking.
Nevertheless, e.g. for having a TDP limit at around 100W the cpu multiplier has to be set at around 3.3 GHz (my guess). With your idea PL2 needs to be set to 3.3GHz as well for all cores.
Donwside: Tasks needing only 2 cores which normally can run at 5.0GHz and drawing way below 100W, unnecessarily would be limited to 3.3 GHz - if I understood you correctly.

Trying to enforce power limits can create instability as the cpu tries in vain to reach its turbo limits, fails, and gets throttled to what the power allows. That can put you on a fine edge of where voltage is needed, demanded, and suddenly isn't there
A valid argument. I could e.g. set a PL2 time to 1-2s in Bios (has no effect on ramping up fans) but preventing a very hard throtteling. Like this no edge should occur concerning voltage needs
 

Hard_ware

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Most Z690 boards will give you access to PL1, PL2 and the turbo time limit in the bios
That is exactly what I would like to find out. Most have it and my question is. Does the MSI Z690 tomahawk DDR 4 Wifi have it?
If anyone can confirm that this board has access to PL1, PL2 power settings and PL2 turbo time limit in seconds I will buy it. If not I need to choose another mainboard which fulfills my requirements.

Thanks for your ideas
 

uWebb429

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Does the MSI Z690 tomahawk DDR4 Wifi have it?
You could always read the manual to find out. :)

http://download.msi.com/manual/mb/Intel600BIOS.pdf

Page 39 and 40 shows Long Duration Power Limit (aka PL1), Short Duration Power Limit (aka PL2), and Long Duration Maintained (aka. turbo time limit). That board has a full featured bios. There are lots of options available but there is no mention of access to the Clamp option which rarely if ever exists in any bios. You need to use Clamp to get your CPU to do exactly what you want it to do.

Edit - Here is a link to the main manual.
https://download.msi.com/archive/mnu_exe/mb/MAGZ690TOMAHAWKWIFIDDR4.pdf
 

Karadjgne

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All Intel mobile CPUs use restrictive turbo power limits to control heat. This technology works great. There are zero stability issues.

All Intel CPUs have used this control method for over 13 years without any stability issues.
Yes, within reason. The multipliers set or stock speeds are set to work within the power limits. As every overclocker eventually finds out, you bump the multiplier too high and don't adjust power, you get instability. Same works backwards. You chop all the power, you need to lower the speeds too.

Op's plan is 80w/100w on a K class 125w/244w cpu. It's not got enough power to even run at base speeds stable. The moment you try even a single core boost... Poof.

A Ryzen would work better in this case as it boosts according to power as well as temp, dynamically. If power is limited, it'll only boost so high, if at all. And doesn't come close to Intels power demands for the most part.
 
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Hard_ware

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You could always read the manual to find out. :)

http://download.msi.com/manual/mb/Intel600BIOS.pdf

Page 39 and 40 shows Long Duration Power Limit (aka PL1), Short Duration Power Limit (aka PL2), and Long Duration Maintained (aka. turbo time limit). That board has a full featured bios. There are lots of options available but there is no mention of access to the Clamp option which rarely if ever exists in any bios. You need to use Clamp to get your CPU to do exactly what you want it to do.
Thank you for bringing this up - unfortunately the Bios.pdf is silent about which values can be applied for the Long Duration Power Limit (aka PL1), Short Duration Power Limit (aka PL2), and Long Duration Maintained (aka. turbo time limit) in the BIOS. In my case I would like to engineer around and start with PL1=80 and PL2=100W therefore I need to find a mainboard which gives me this option.

For info: I am sitting at a PC which I cannot hear in 1,5m distance under full CPU load of 95W (Prime 95)
 

uWebb429

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I need to find a mainboard which gives me this option.
The two turbo power limits are adjustable from 0 W to 4095 W.

It's not got enough power to even run at base speeds stable. The moment you try even a single core boost... Poof.
A stable CPU can run any load, at any speed and at any power limit without going poof. The power limits can change dynamically whether the CPU is idle, partially loaded or fully loaded. If a CPU cannot do this then the settings you are using are not stable.

Here is my 10850K running 10 threads of Prime95. The power limits are set to 0 and the Clamp options are checked so this forces the CPU to throttle down to its minimum speed, 800 MHz.

It is not crashing or going poof. It is chugging along, while it is being power limit throttled. The CPU is trying to get power consumption down to the requested value of 0 W. This of course is impossible so instead it slows down to the minimum CPU speed.



All Core i Intel CPUs are controlled by these two power limits. A CPU coming down the assembly line does not know if it is going to become a CPU with a 65W TDP rating or a 125W TDP rating. After the CPU is produced, Intel writes a default TDP value to the CPU. At default settings, the BIOS is supposed to set the turbo power limits based on the rated TDP value.

Whether Intel sets these power limits or whether the BIOS sets these power limits or whether a user does this by using software makes zero difference. All Intel CPUs must comply with whatever power limit values are stored in the power limit control register. Whether this register is set to 65W or 80W or 100W does not matter. The CPU will constantly adjust its speed hundreds of times per second to make sure that it does not exceed whatever power limit that has been set.

This is very old technology now. It has been around since 2008 when the first Core i was introduced. I think Intel has a good handle on the reliability and stability of their power limit throttling algorithms.
 

Hard_ware

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Op's plan is 80w/100w on a K class 125w/244w cpu. It's not got enough power to even run at base speeds stable. The moment you try even a single core boost... Poof.
For clarification I will use a 12700K 125W/190W CPU (not a 12900K) which I intend to have restricted most of the time to PL1=80W and PL2=100W.
And with 100W you can have around 4 Cores at full turbo boost because each P core draws around 20W at 4,8Ghz.

But it is even better:
Please have a look at the Perfromance table of a tested 12900K with different Power limits applied
It is in German, but the table does not need any words. E.g. A 12900K with power limit of 88W has only 20% less performance than the same 12900K in stock configuration 125W/244W.

Therefore I should loose even less than 20% max performance for an 12700K used at 80W/100W compared to stock 125w/190W.
I am happy to accept this minimal performance loss gaining a close to not audible PC.
 
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Here is my 10850K running 10 threads of Prime95. The power limits are set to 0 and the Clamp options are checked so this forces the CPU to throttle down to its minimum speed, 800 MHz.
Thank you for this demonstration - great tool.
I think a 10850k has PL1, PL2 125W/250W.
If this CPU is clamped to 100W I expect you to loose around 20-25% in e,g, Cinebench only (close to zero loss in single)- If you have an air cooler and a good fan curve you will notice very much reduced rpms.
Maybe you like to try it out? Then you can directly experience the loss in performance and gain in a quiter PC. Would you like to give us a feedback?
 

Karadjgne

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20% performance loss. So why bother with such a powerful cpu in the first place? Just interested. My 3700x runs silent unless I Prime95 it. Granted it's a 65w cpu to start with, tweaked for max efficiency, and gets higher than stock performance in cinebench, multi or single thread. And doesn't go beyond 66°C. The loudest component is the ddc pump, and thats barely audible further than 3 feet away and only under excessive loads when I ramp up the rpm for more flow.

Case design, case fans, airflow patterns, hotspots, insulation and batting, heat sources, they'll have a lot to do with silence, not just limiting power to the cpu.
 

uWebb429

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20% performance loss. So why bother with such a powerful cpu in the first place?
Reasonable question: I need 8 P Cores 1-2 days every 14 days. For these tasks I will set no power limit for the CPU. Otherwise I need the PC to be very quiet - besides 4K gaming and VR :)

Case design, case fans, airflow patterns, hotspots, insulation and batting, heat sources, they'll have a lot to do with silence, not just limiting power to the cpu.
You are completely right. Therefore I will buy an insulated case, Dark Rock 4, be quiet silent wings 3 for the case, Corsair 1000W PSU with silent mode up to 500W, only SSDs inside.
Did I forget something? What do you mean with batting?
 

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