News Intel Core Ultra Series 3 CPUs could finally answer AMD's V-Cache — Nova Lake could boast massive 144MB L3

[TerryLaze]

disabling LPE/LP cores in BIOS could be the quick fix,

Is that even possible?! If they are there to wake up the other cores they might not give you the option even if you technically could.

 

[usertests]

Is that even possible?! If they are there to wake up the other cores they might not give you the option even if you technically could.

It's not like they are the Management Engine core deeply embedded into each processor.

I looked around and here's someone doing it for Meteor Lake: https://blobfolio.com/2025/fixing-intel-meteor-lake/

The guy disabled the two LPE-cores with a max frequency of 2100 MHz. He appears to have been using a top-of-the-line Core Ultra 7 165U (4900, 3800, 2100 MHz boosts), and has miscounted 12 cores as 14 cores (the P-cores have hyperthreading).

 

[thestryker]

If the scheduler uses them properly, lowering idle power is a great reason to include them in desktop. Lots of energy and money will be saved across tens of millions of users.

Current CPUs barely use power at idle this is just a rounding error. The problem with idle at this point is basically everything else in the computer. For enthusiast users the motherboard, video card and fans probably use more power than the CPU idling.

Switching to 12VO would also do more than any CPU level changes. There's a reason OEMs were already using their own versions of this before the spec was set.

In the case of AMD ditching the dual chipset design would do the most to drop idle power consumption.

 

[usertests]

Current CPUs barely use power at idle this is just a rounding error. The problem with idle at this point is basically everything else in the computer. For enthusiast users the motherboard, video card and fans probably use more power than the CPU idling.

Idling isn't completely idle after a bunch of junk is installed and running in the background. "Rounding errors" add up.

But if the workload is light enough, it could be run entirely on efficient low power cores that are being utilized up to but not exceeding 100%. For example, watching streaming video. An iGPU's video decoder should be handling hardware accelerated video playback, but there are some elements that are using the CPU, especially in web browsers (e.g. live chat, or God forbid, ADVERTS).

Power gating the unused CPU chiplets/tiles reduces leakage and power draw. If P-cores are needed, they can presumably come back online within a few milliseconds, imperceptible to the user. It might be possible to predict this and turn it on sooner, based on user actions.

Leaks have pointed to different amounts of low power cores coming to Intel and AMD desktop CPUs. They might start out with 2 cores, but expand to 4 cores later. After some die shrinks it could even be 8 tiny cores, still using barely any die space at all. AMD's implementation is likely to have 2-way SMT. Increasing what it can handle will allow CPU chiplets/tiles to remain turned off longer.

The majority of PCs globally don't have dedicated graphics and don't need it. This is true for most office PCs that don't need workstation graphics capabilities or to handle dozens of video streams simultaneously, etc. By the way, the Core Ultra 5 245T for low-power desktops and office PCs has faster graphics than the Ryzen 7 5700G desktop APU. Arrow Lake-S doesn't have any LPE-cores, but it looks like Nova Lake-S will have 4 of them, padding the max core count up to 52.

 

[thestryker]

Idling isn't completely idle after a bunch of junk is installed and running in the background. "Rounding errors" add up.

But if the workload is light enough, it could be run entirely on efficient low power cores that are being utilized up to but not exceeding 100%. For example, watching streaming video. An iGPU's video decoder should be handling hardware accelerated video playback, but there are some elements that are using the CPU, especially in web browsers (e.g. live chat, or God forbid, ADVERTS).

Power gating the unused CPU chiplets/tiles reduces leakage and power draw. If P-cores are needed, they can presumably come back online within a few milliseconds, imperceptible to the user. It might be possible to predict this and turn it on sooner, based on user actions.

Leaks have pointed to different amounts of low power cores coming to Intel and AMD desktop CPUs. They might start out with 2 cores, but expand to 4 cores later. After some die shrinks it could even be 8 tiny cores, still using barely any die space at all. AMD's implementation is likely to have 2-way SMT. Increasing what it can handle will allow CPU chiplets/tiles to remain turned off longer.

The majority of PCs globally don't have dedicated graphics and don't need it. This is true for most office PCs that don't need workstation graphics capabilities or to handle dozens of video streams simultaneously, etc. By the way, the Core Ultra 5 245T for low-power desktops and office PCs has faster graphics than the Ryzen 7 5700G desktop APU. Arrow Lake-S doesn't have any LPE-cores, but it looks like Nova Lake-S will have 4 of them, padding the max core count up to 52.

None of this actually adds up to any notable amount of power consumption at the wall. Consider that a single fully loaded ARL P-core is going to have the CPU pulling ~25W on the most powerful SKU. The vast majority of systems won't even see idle power consumption that low unless they're using mobile parts. The CPU at low usage simply is not a big enough portion of power consumption on desktop platforms to justify adding LPE-cores to the design.