i9-12900KF missing L1 & L2 cache

[lamppost]

I bought this CPU and built my PC this April. Today I was playing around and found out that on ark intel that 12900KF has 14MB of L2 Cache. A quick check on task manager shows mine has 12.5MB

Then I checked on Intel Processor Identification Utility and HWiNFO for reassurance

Here you can see my e-core's L1 is 8x32+8x48, though various sources (e.g. a user on reddit), it should have been 8x64+8x32.

This is also the case for e-core's L2, it is 2x1.25MB instead of 2x2MB. That means 8x1.25+2x1.25 = 12.5MB, so I am missing 1.5MB of L2.

Here is my system information
Intel core i9 12900KF, stepping 2, MCU 34; I do have the box if you need batch number and S/N
Asus TUF gaming z790 plus Wi-Fi d4, bios version 1658.

Thank you for your help, Intel moderator!

[pressed_for_time · Accepted solution]

As a user of Intel hardware I have come across this issue myself. It is more likely that incorrect values are being displayed rather than there being anything wrong with the CPU itself.

Part of the solution is to upgrade to the latest drivers and BIOS for your motherboard. For drivers I would recommend updating to Chipset driver v10.1.19913.8607,  Management Engine Interface v2428.6.2.0 and Serial IO Software v30.100.2417.30 in that order and before updating the BIOS.

The latest BIOS is 1820 dated May 21 2025.

I prefer to use CPU-Z from CPUID to display processor information, it is a free utility that can be downloaded from here .

[lamppost]

Hi pressed_for_time! Sorry for late reply. I've been busy finding a USB to update BIOS.

I have reinstalled your version of Chipset Driver, Management Engine Interface and Serial IO Software. After that I updated the BIOS to 1820. Unfortunately, the problem still persists on the newest version of Windows 10, every tools and even Windows still reported the wrong info. I tried CPU-Z and it was the case too.

CPU-Z report shows wrong L1, L2 cache

Therefore, I went to Ubuntu 24 to check. I tried lscpu, which showed the correct config

lscpu command

Though people said lscpu is not reliable enough, so i tried dmidecode, CPU-X (A linux CPU-Z version) and lstopo

CPU-X performance cores L1, L2

CPU-X efficiency cores L1, L2

lstopo's graphical interface

They also reported the right L1 and L2.

I should have told I use Windows 10 beforehand, I heard it has some weird bugs on big little architecture but not this weird cache bug.  

Cheers! And thank you for your help!