Question i9-12900

cAllen

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Little confused on the new cpus. Does the core speed always idle at 2.4 unless it throttles for demand...or can I just set it to idle at 3.2. The K version runs at 3.2 steady state idle and still throttles for demand, so not sure if I'm crossing my wires with how OC works now compared to days past. In other words...if I buy an i9-12900 am I just getting a 2.4 GHz cpu?
 
Little confused on the new cpus. Does the core speed always idle at 2.4 unless it throttles for demand...or can I just set it to idle at 3.2. The K version runs at 3.2 steady state idle and still throttles for demand, so not sure if I'm crossing my wires with how OC works now compared to days past. In other words...if I buy an i9-12900 am I just getting a 2.4 GHz cpu?
Cpus could be said to have 3 modes; base, turbo and overclocked. The 2.4 base speed is sort of the forever speed that the cpu is guaranteed not to fail at. Then you just change some settings in you bios and you get turbo speed which is "Max Turbo Frequency is the maximum single-core frequency at which the processor is capable of operating using Intel® Turbo Boost Technology and, if present, Intel® Turbo Boost Max Technology 3.0 and Intel® Thermal Velocity Boost. Frequency is typically measured in gigahertz (GHz), or billion cycles per second. " That's 5.1, Then you can change additional bios setting which your motherboard manufacturer has included in the bios to get higher speeds which may be as high as 5.5. Idle speed depends on how you set your bios for things like Intel Speedstep and other factors.
 
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The operating speed of a processor is variable.
If you implement speedstep, in windows power management, you change the minimum processor operating speed from 100% down to perhaps 20%
When there is little to do, the cpu will idle at 20%.
When a load hits it, it will instantly jump to a much higher number.

Overclocking is no longer a way to get something for nothing.
Better chips will have higher turbo limits.

For gaming, the turbo boost will boost a couple of cores past that an all core OC can deliver. That is what games need most.
Overclocking all cores may be better for batch operations where all cores can be fully saturated.
 
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cAllen

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Going from a X3380 to the current tech is different. I just want stable, fast, top of the line like I did back in 2009. OCing for bragging rights (or whatever) was never then or what I want now, but I do want the rest to replace this 13 YO referenced build on my new. Seemed more appropriate to address my CPU ignorance here.


Thank you for ALL previous, current and future comments and recommendations.

BTW geofelt, how's that NH-D15 doing on your i9-12900k? I only ask because I will soon have to decide between liquid and air.
 
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BTW geofelt, how's that NH-D15 doing on your i9-12900k? I only ask because I will soon have to decide between liquid and air.

I have no personal experience, but here is a quote I found a couple of months ago about a 12900K on a single tower Noctua U12A. Based on this quote, I wouldn't think you'd have a problem in normal circumstances with the superior D15:


"I'm running a 12900k on a u12a, I get 70 to 72C on cinebench R20 and around 75-78 on cinebench r23. That's at 204 to 230 watts."
 
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Going from a X3380 to the current tech is different. I just want stable, fast, top of the line like I did back in 2009. OCing for bragging rights (or whatever) was never then or what I want now, but I do want the rest to replace this 13 YO referenced build on my new. Seemed more appropriate to address my CPU ignorance here.


Thank you for ALL previous, current and future comments and recommendations.

BTW geofelt, how's that NH-D15 doing on your i9-12900k? I only ask because I will soon have to decide between liquid and air.
Actually, it is a NH-D15s.
The s variant is the high compatibility version.
In normal usage, I never hear it. The pc on the side of my desk.
Under testing loads, like the cpu-Z stress test, I will see three cores reach 100c.
No doubt there is some throttling going on for only those three cores, but the chip keeps running.
The cpu fan will run at 1500 rpm which is really not noisy.
My two 140mm front case intakes run at 800 RPM, I suppose they could do more.
In actual use, like for games, it is hard to push all cores so the chip normally really loafs.

The potential capability of any cooler is determined by the cooling fin volume it has.
NH-D15 twin stack will have about the same fin volume as a 280 aio radiator.
And, you need good case airflow to feed either type of cooler.

In summary, I am pleased.