With the arrival of the 12th-generation Intel Core processor code-named Alder Lake, we hope to see many new technologies packed into one package.Today, according to Core boot Patch (via Dream of coelacanth), we saw some first-hand information about the different power states and power limit 4 (PL4) levels of the upcoming Alder Lake-M and Alder Lake-P designs.
Coreboot is an open source solution designed to replace millions of proprietary BIOS implementations. This project aims to boot 32-bit and 64-bit operating systems on bare metal (ie, hardware) with minimal functionality, making it a lightweight alternative to BIOS. Today, the latest patch of this software project brings us some information about the Power Limit 4 (PL4) of the Alder Lake P/M processor, which is different from the previous generation Tiger Lake it is replacing.
The new information is related to the two Alder Lake processor series displayed on the Brya platform, which is the reference verification platform for Chromebooks. One is Alder Lake-M, which is an ultra-low power range CPU, in this case designed for 5-7W TDP, and the other is Alder Lake-P, which represents a processor with a 15-watt TDP. Note that there are other power envelopes in the brackets of M and P, so they are not shown here.
From some perspectives, you must note that PL4 is the maximum power limit that the SoC can reach. This is a non-permanent power value that the CPU avoids at all costs and can only last for a short time before the CPU shuts down. Before PL4, there are other levels, such as PL1, which represents the TDP of your processor, PL2, which is the maximum boost frequency level, and PL3, which slightly restricts the CPU to remain usable, and PL4 functions even encounter defined limitations.
In the table below, you can notice the value of the Alder Lake processor compared to the previous generation Tiger Lake design. Please note that there are four SKUs: Alder Lake-P (2+8+2), Alder Lake-P (4+8+2), Alder Lake-P (6+8+2) and Alder Lake-M (2 +8+2). Each number represents the number of large cores, the number of small cores, and the level of integrated graphics. In this case, the GPU is at the GT2 level, which is a configuration with 96 execution units (EU).
|Tiger Lake-U||Tiger Lake-H||Alder Lake-P||Alder Lake-M|
|PL1||UP3: <= 28W UP4: <= 9W||<= 45W||(2 + 8 + 2): <= 15W | (4 + 8 + 2): <= 28W | (6 + 8 + 2): <= 45W||(2 + 8 + 2): <= 9W|
|PL2||UP3: <= 38W (2C), <= 60W (4C) | UP4: <= 35W (2C), <= 40W (4C)||107-135W||(2 + 8 + 2): <= 55W | (4 + 8 + 2): <= 64W | (6 + 8 + 2): <= 115W||(2 + 8 + 2): <= 30W|
|PL4||UP3: <= 71W (2C), <= 105W (4C) | UP4: <= 66W (2C), <= 83W (4C)||(2 + 8 + 2): <= 123W | (4 + 8 + 2): <= 140W | (6 + 8 + 2): <= 215W||(2 + 8 + 2): <= 68W|
As you can see, in the configuration shown, the Alder Lake-P PL4 value can be as high as 215 watts. This does not represent all SKUs, as some may be higher. For Alder Lake-M, it “only” reaches 68 watts. These values should not exceed 10 milliseconds, because the laptop battery and charger are not designed to withstand longer periods of time. Therefore, PL4 is restricted.
Adding this small piece of information to the information wall indicates that we are on the cusp of the upcoming release of Alder Lake.