Code name Alder Lake, large and small core design Intel Core i9-12900K processor architecture analysis + evaluation

 Intel officially released the code-named Alder Lake, the 12th-generation Core processor, using the new Intel 7 process (10nm), adding the P-Core / E-Core large and small core hybrid architecture to the Desktop platform for the first time. Compared with the previous generation IPC, the performance is improved by 19 %, single-core performance beats AMD Zen 3, multi-core performance is similar, and claims to regain the title of the strongest gaming CPU. The HKEPC editorial department will analyze the internal design improvement of the Alder Lake processor and find a new Intel Core i9-12900K for processing The sample of the device, compared with the previous generation Core i9-11900K and the rival AMD Ryzen 9 5950X.

Alder Lake: Intel's 12th-generation Core processors debut

The toothpaste factory is finally working hard!! Intel officially released the code-named Alder Lake, the 12th generation Core processor, using the new Intel 7 process (10nm Enhanced SuperFin), Hybrid small-core hybrid architecture application on the Desktop platform, and the introduction of the new PCIe 5.0 and DDR5 specifications, Intel claims that the performance of Alder Lake processors has increased by an average of 19% compared to the previous generation Rocket Lake. IPC performance has once again surpassed AMD Zen 3 processors, returning to the throne of the best gaming CPU that Intel has always been proud of, CEO Pat Gelsinger It also said: "The era of AMD is over."

 

Intel held the "Intel Architecture Day 2021" architecture analysis meeting earlier. This article will share the design highlights of the Alder Lake CPU architecture, including:

→ Alder Lake SOC brand new Building Blocks design

→ New Golden Cove micro-architecture P-Core design with performance first

→ New Gracement micro-architecture E-Core design with high power and energy efficiency ratio

→ Add Thread Director command scheduling unit for large and small core architectures

→ Add PCIe 5.0 x16 interface, support new DDR5 memory

Mixed large and small cores: Alder Lake SOC configuration

 

▲ Intel Alder Lake 8C+8c Die Shot

The biggest reform of Intel's 12th-generation Alder Lake architecture is the addition of a hybrid core design similar to ARM's big.LITTLE. The big core is the Performance core (P-Core), which is mainly used for high-priority single-threaded work or more complex The small core is the Efficiency Core (E-Core) for multi-threaded workloads, less complex background tasks, back instructions, I/O instructions, etc.

 

Intel's 12th generation Alder Lake processor adopts Building Blocks design, which can meet different markets through the mix and match of IP modules. It consists of Ultra Mobile processors (BGA Type 4 HDI) with a minimum 9W TDP and 12W to 35W Mobile processors (BGA Type 3). Up to 125W Desktop processor (LGA 1700).

The dark blue in the picture is the Golden Cove (P-Core) core (red), which supports Hyper-Threading technology to charge a single core to operate two threads at the same time. The lighter color is the Gracemont (E-Core) core (yellow) does not support Hyper-Threading. The computing power of E-Core is equivalent to Sky Lake but it saves chip area. Intel data shows that 4 E-Core cores are equal to 1 14nm Skylake core. Different Core, L3 Cache (LLC) and other IP modules use Ring Inter-connection The ring bus is linked together.

 

All Alder Lake version processors are equipped with Media media engine, GNA 3.0 Gaussian Neural Accelerator, but the Desktop version of Alder Lake does not have a built-in IPU unit, (TBT) Thunderbolt 4 unit. In terms of IGP, because Desktop users tend to use discrete GPU graphics cards, the Desktop version only has 32 EU (GT1) graphics cores, and only the Mobile processor will have 96 EU (GT2) graphics cores.

 

 

The highest model of the current desktop version of the Alder Lake processor is Core i9-12900K. It has 8 P-Cores, 8 E-Cores (8+8), a total of 16 cores, 24 threads, 30MB L3 Cache, and chip size At 209mm², there are only six models that will debut temporarily, including Core i5-12600K/KF, Core i7-12700K/KF, Core i9-12900K/KF, and other models will be available at the end of January 2022.

 

 

 

First to support DDR5 / PCIe Gen 5

As for memory controllers, Alder Lake processors will add support for DDR5 processors, starting from DDR5-4800 to a maximum of DDR5-8400. It has been learned that DDR5 will only be supported on the high-end Z690 platform, from entry to mainstream level H610 / B660 / H670 will still use DDR4 memory, which seems to be due to the higher initial price of DDR5 memory modules.

The desktop version of Alder Lake processor has built-in 28x PCIe Lanes. The graphics interface is upgraded to PCIe Gen 5 x16 Lanes, which doubles the maximum bandwidth compared to Gen 4 to 64GB/s. A set of PCIe Gen4 x4 Lanes is also provided. Used to connect to NVMe SSD.

 

The connection between the processor and the Z690 PCH system chip is upgraded from DMI 3.0 x8 to DMI 4.0 x8, and the speed is doubled from the previous generation up to 8GB/s to 16GB/s. This is for users who build Gen 4 M.2 SSD RAID , To reduce the chance of speed bottlenecks in continuous reading and writing.

In terms of internal connections, Alder Lake processors use Dual Ring Inter-connect Bus inline, with a total bandwidth of up to 1000 GB/s and very low latency. This is why Intel rarely has I/O when the CPU is fully loaded. For latency issues, the CPU can shut down one of the Ring Bus to reduce CPU power consumption in response to computing needs.

The bandwidth of I/O Fabric is provided up to 64GB/s, mainly for the highest bandwidth requirements of the new generation PCIe Gen 5 x16, but it is puzzling that the bandwidth of Memory Fabric is increased to 204GB/s. It is necessary to know the highest memory of Alder Lake The frequency divider is only DDR5-8400, and the 128bit Dual Channel is only used up to 134.4GB/s. I don’t know why Intel’s Memroy Fabric is so exaggerated.